Food: The Art & Science of Roasting Seeds & Nuts, by Robert Fuller

Roasting, in the context of this article, mainly refers to the roasting of nuts and various seeds, such as sunflower, pumpkin, and squash, as well as an assortment of other seeds that are usually thought of as belonging to the herbs & spices category.

While you can certainly roast seeds & nuts even if the package says they’ve already been roasted—I’ve done this on numerous occasions, truth be told—if you really want to see how this works, find a supplier of raw nuts & seeds, such as this example from Lucky. Most of the items you buy will not only not have been roasted, but in general they also will not have had anything else added to them. The one exception that comes to mind is the squash seeds (in-shell) that I have bought recently; out of the package, they were both roasted & salted.

Now, the in-shell squash seeds were an exception to the rule, as to how to prepare them. (More about that later.)

The general modus operandi for preparing delicious roasted nuts & seeds is this: Use an air fryer! That may sound preposterous to some, but I’m not referring to a standalone air fryer; after all, I’ve never tried that for air-roasting seeds or nuts.

No, the air fryer I recommend, because it has actually worked really well for me, is the one that comes bundled with various Hamilton Beach toaster ovens. They’re the 4-in-1 types, the ones that include bake, toast, air fry, and broil settings.

The model I have—which was probably the most inexpensive of the 4-in-1 part of their product line—has truly worked wonders for me.

Okay, that’s enough of a plug for now. Hamilton Beach—(no, no, not the musical!)—it’s time to take your bows!

The first thing you need to know, once you have your Hamilton Beach 4-in-1 toaster oven fired up and ready to go, is that your roasting temperatures and times will vary according to how delicate the nuts or seeds that you’re roasting are. (Delicate, in this context, refers not only to the relative fragility or density of the item, but also to its size. The smaller items, in general, will want to be roasted at lower temperatures!)

The second rule of thumb, if you’re not sure of the ideal temperature, is to start at a reasonably low temperature. You can always adjust the temperature upward if needed. But you don‘t want to start at too high a temperature, because if you do, you may end up browning or even burning your nuts or seeds more than you would like!

Proceed with caution, then.

Your third rule of thumb is that, using your toaster oven’s “air fry” setting, you will do your air-roasting in five minute increments. The primary reason for this is that you will want to monitor how the roasting process is getting along. Now, you should also be aware that you could have used your toaster oven's “bake” setting. The main reason that you’re not doing that is that air-roasting takes less time! Yes, we all know how busy you are, how packed to the gills your schedule is—and we all empathize, deeply, believe me. Yet, here’s the thing: It’s also true that air-roasting gives you at least as good, if not better, results.

A fourth rule of thumb is this: Before you do anything with the nuts or seeds of your choice, first try dry-roasting them! Dry-roasting simply means that you're not adding anything to the seeds or nuts prior to the roasting process.

As an adjunct to that rule, in order for you to begin to understand the time and temperature requirements for whatever it is you’re roasting, the general rule of thumb is that you should do dry-roasting on the item for five minutes, starting at a relatively low temperature, after which you should examine and taste the results. You can repeat these instructions until you’re just about satisfied that you’re about to hit that proverbial sweet spot.

If you were going to consider adding other items to your roasting adventure, you would want to add them right after hitting the sweet spot.

Fifth: Once you’ve done the dry-roasting just so, if you’re planning to add extra goodies to the mix, you should add them first, and then make sure you mix everything together thoroughly. This is especially true of olive oil or other liquid substances. You need to spread the love! But you already knew that, didn’t you? It’s not just true of the liquids, but also of anything else you add to this stage of the roasting process. This includes herbs & spices in powdered form, or anything else that you add. The point is to get the extra goodies distributed as evenly as possible. (Think about it: That's a profound socio-economic statement! Jesus would be proud...)

It's also prudent to lower the temperature a notch or two once you’ve added extra goodies to the mix. You should continue to air-roast in five minute increments, and you can test and taste the intermediate results in the interim. If you think the temperature should be increased next time around, try it out! But you will continue to monitor how the item you’re roasting looks and tastes, and then you will finally, hopefully find the taste sensation you’ve been seeking.

A final rule of thumb, one that applies to all stages of your roasting adventure, is that you should allow a little window of time in between each 5-minute roasting session and the next. The reason for this is that once the five minutes is up, there is still heat in your Hamilton Beach toaster oven, which means that the roasting is still happening. And you can only really monitor the progress of your roasting masterpiece after things have cooled down a bit.

The final proof of that proverbial eating of the pudding is simply this: Taste the final results after your masterpiece has cooled down sufficiently. The flavor, color, and degree of doneness should be just about perfect. (On the other hand, there are certain instances where you may wish to delight in your roasted seeds or nuts while they’re still hot, either on their own or as part of another dish.)

Now for the exception to the rule for roasting seeds & nuts: in-shell squash seeds. While it’s true that you can use the same modus operandi already described, for in-shell squash seeds (or, for that matter, for in-shell pumpkin seeds), the alternative way is really tasty, if done right.

It’s simple: Just pan-fry them in butter. What this does for any of your in-shell seeds is not only to add a nice crispiness to the shells, but it also makes them just a tad more tender. And most importantly, it gives them a really nice, almost irresistible aura of buttered popcorn! When you pan-fry them, you should stir frequently, with the aim of trying to get the seeds browned as evenly as possible, and you should also taste the intermediate results now and again. (Isn't cooking fun!?) And don't forget to turn the stovetop fan on, open a window or door, adjust the heat every now and then, and that sort of thing, so the darn smoke detector doesn't start piercing your ears. You know the drill by now; this isn't your first rodeo on a one-trick pony, after all. Is it!?

This brings up another important point: When you use the air-roasting method, you can add extra ingredients to the latter stages of the roasting process. You could conceivably add them at the very beginning, but I usually prefer to try the dry-roasting first, since it's a really useful basis for comparison. This general approach is something that I try to use whenever possible in just about any of the cooking, baking, or roasting I do, the idea being that, to whatever degree possible, taste each of the individual ingredients on their own—raw, if possible. This applies to all ingredients, including herbs, spices, ferments, and sauces, in addition to fruits and vegetables. (There are obvious exceptions to the stipulation that you taste ingredients when they're raw. These include meats of all kinds, as well as certain mushroom varieties. Most of the commonly available mushrooms from your local farmers market or the supermarket are safe to eat raw, but there are certain varieties that your friend the internet will tell you should not be eaten raw. So please use your own good judgment regarding raw foods, along with the help of reputable websites.)

The reason for tasting ingredients individually is much the same as the tasting of dry-roasted seeds or nuts prior to adding anything else. It’s to give you a basis for comparison. And, if you are not averse to tasting the raw nuts & seeds themselves, to do so would be yet another basis for comparison; you could try the raw version first, and then compare it to the dry-roasted version.

This brings us to the next topic, that of add-ons.

Three of the most commonly used and popular ingredients are extra virgin olive oil, sea salt, and black pepper, either singly or in various combinations. The combination of all three is a well regarded go-to for many dishes, whether in cooking, roasting, or any other type of food preparation.

You can also add other herbs & spices, either singly or in various combinations. This is where your taste-testing of all those individual ingredients comes in handy. The idea is to use your taste buds and your olfactory sense to clue you in on the primary one of the 5 basic tastes that best characterizes each ingredient: sweet, sour, salty, bitter, and umami.

If you want to buy herbs, spices, and other fun items at wholesale prices, check out SF Herb Company. Because of the bulk amounts, you may want to find like-minded foodies or partners in crime to split—legally procured, of course—your booty with. (Or, if you're adept enough at the door-to-door sales thingy, you could consider getting all your foodie neighbors involved monetarily with your newest side hustle. You know, get them to cough up an insignificant portion of their hard-earned loot so as to make their every repast just that much more toothsome.)

The better you become at decoding this facet of your herbs & spices (and other ingredients), the more capable you will be in figuring out interesting and unique flavor combinations for your roasting—and for pretty much all of your other food preparation activities.

There's an easy way to think about flavor combinations that simplifies the art of flavor combining to just two basics. These are, of course, our friends sweet and savory. So in your roasting activities—and in all of your other food-related activities—you should consider the broad brush-stroke question, “Do I want this to be savory, sweet, or both?”

For instance, if you have done your homework, you should already know that there are quite a few herbs & spices that register quite prominently on the sweet side of the spectrum. These include, among others—and these are all either dried, powdered, or both—basil leaves, marjoram, cinnamon, nutmeg, cloves, and probably many others.

The ones that are generally considered to be savory include many different flavor variants, which is one of the main reasons I’m so often drawn to this side of that bipartite spectrum, even in foods that are usually categorized as desserts or “sweets”. They can be as widely varied as turmeric powder, onion powder, garlic powder, dried thyme, ancho chili powder, saffron, dried parsley, ground cumin, paprika—well, you get the picture. There’s lots of them. And some of them share both sweet and savory characteristics.

Now, with regard to the 5 basic tastes—if you think about it, there are certainly others. At the very least, there’s spicy. Who among us doesn't know the tongue-, mouth-, and throat-burning sensations that we experience with cayenne pepper, for example? And then your sinuses get cleared out and eventually you get over it. But this is a handy tool to have in your flavor arsenal, especially if, as with other spices like turmeric, you use it sparingly. Yes, you give your dish just the slightest hint of flavors that in lesser hands could easily overpower, and it gives that gustatory masterpiece of yours that je ne sais quoi air of mystique and intrigue. They’ll never figure out how you did it! And the culinary critics will be lining up right outside your balcony like paparazzi following Taylor Swift’s every move! And then you go viral, like everyone wants to!

While you’re at it playing around with herb & spice combinations, do yourself a favor, and at least take mental note of your favorites, or even better, keep a diary or journal or blog about all of that. Or become one of those—how do you say—social influencers.

In addition to all of those fabulous herbs & spices—and we’ve barely even scratched the surface, in terms of the ones that have been mentioned thus far—the question begs: What about that umami!?

Okay, what about it?

According to various internet sources, such as healthline, there are numerous foods and ingredients that are graced with umami. And they're divided into several different categories.

But the main type of umami ingredients I’d like to cover for now are the many different ferments, many of which are based on soy sauce. When added to the roasting of seeds & nuts, they can dramatically increase and complement whatever other add-ons you've already added to your soon-to-go-viral epic wonderment of exquisite, piquant tastiness.

There’s a very good book about ferments that I just have to hawk: The Noma Guide to Fermentation. Written by René Redzepi and David Zilber, it’s first and foremost a guide for how to do your own fermentation, but there's also an excellent list of store-bought items in most of the seven categories of ferment that they cover: kombucha (this one isn’t covered in the store-bought alternatives, for some reason), vinegar, koji, miso, peaso, shoyu, and garum. (Actually, there are nine categories, but the store-bought alternatives are covered for only six of them. The other two categories besides the seven already mentioned are lacto-fermented fruits and vegetables; and black fruits and vegetables, such as black garlic. That last category is based largely on fruits and vegetables that have been caused to caramelize.)

The list (of those store-bought alternatives) given by Redzepi and Zilber, on page 52 of the bound volume, is as follows:

  • Vinegar: Traditional balsamic vinegar

  • Koji: Dried rice koji

  • Miso: Hatcho miso

  • Peaso: Okasan miso

  • Shoyu: Raw shoyu

  • Beef garum: Worcestershire sauce

  • Rose and shrimp garum: Fish sauce (Red Boat brand)

I’ve used at least five items or rough equivalents from the list, namely, balsamic vinegar, koji, miso, Worcestershire sauce, and Red Boat fish sauce. I’ve also used (Kikkoman) soy sauce and other soy-based sauces, including Ponzu, which is awesome. Ponzu is a soy-based sauce with a citrus twist. I’ll go into some of my favorite sauces, ferments, and other umami-related items in another article.

For the more daring and enterprising among you, maybe you’ll even try making some of the many different ferments listed in great detail in the book. I haven’t been so bold as yet, mostly because I’m a bit intimidated by the fact that if you don’t know exactly what you're doing when it comes to fermentation, you might do an experiment that gets contaminated by harmful microorganisms, which in my estimation would be a complete bummer or worse. My take on the whole fermentation thing is that it might be prudent to study the subject directly, in person, with a true master.

On the other hand, there’s what appears to be a really comprehensive list of equipment that’s required for the pros in this field, and lots of details about how to make it work properly and safely, so some of the more astute among us might well be able to immerse themselves in the art & science of fermentation just by carefully following the detailed instructions in this book.

(Now for a sidebar to plug the excellent and fun NPR radio program The Splendid Table, currently hosted by the magnificent Francis Lam. The first link—“The Splendid Table”—is for Episode #755, which is all about those special umami-packed sauces. The guests include the venerable René Redzepi—who you've already met—, Diep Tran, and Khushbu Shah. Please have a listen! You won’t regret it!)

Back to roasting: As with any add-on ingredients, if you add ferments or sauces or other umami-related ingredients to the mix, you should stir and mix everything together so as to spread the love. That’s our mantra.

Butter: You can use this at one of the later stages of the air-roasting, whether you’ve already used olive oil or not. If you do add butter during the last part of the roasting, once you taste the results, it’s very likely that you'll wish you were at the movies. It’s called Buttered Popcorn Syndrome! (BPS! Yes, it’s a real thing, or at least it will be once we get enough people listening to me. As far as I know, it hasn’t happened yet... Y’all go out there and help me with this.)

There are other ingredients that you can consider adding, either singly or in various combinations. As with anything you add to your roasting artworks, you should initially add ingredients like this sparingly, at first.

One of my go-to ingredients, for baking especially, is dark chocolate—in particular, unsweetened chocolate—such as some of my favorite chocolates, which are made by Lindt. I don't think I’ve actually used chocolate yet in my nut & seed roasting, but it's certainly tempting. (It might be easiest to use chocolate in a powdered form. I’ll bet that works great!)

Another ingredient that can turn out awesome, whether used sparingly or liberally, is real maple syrup. If you use it liberally, you’re going to end up with the seed or nut counterpart of peanut brittle, but with a richness that only maple syrup (or a similar awesome sweetener) can provide. If you use it sparingly, hopefully you’ll add just the right tinge of sweetness to your roasting tour de force. My inclination would certainly be to make it part of a sweet-n-savory flavory combination, perhaps in cahoots with onion powder or garlic powder. And... Butter!

We could go on and on about all of the add-on possibilities, but I think you’ve already gotten the main point. So now it’s back to cookbooks for just a minute.

I won’t steal the thunder from this marvelous tome by Samin Nosrat—it’s called Salt, Fat, Acid, Heat, and in my humble estimation it’s a must-have for budding young cooks of any age—except to say that it’s enlivening and inspiring, and features a systematic treatment of the art & science of cooking with plenty of hand-drawn illustrations, diagrams, and so forth that I find just captivating. (The artwork is by Wendy MacNaughton, by the way.)

Now, y’all just have yourselves a very merry, happy Christmas, or New Year, or Groundhog Day, or Valentines Day, or Easter, or birthday, unbirthday, or any other celebration of choice, and treat yourself and all your family and friends to the two aforementioned awesome cookbooks! You won't regret it! You know your inner foodie wants it! This is how to win friends and influence people!

Finally, the last and perhaps most important part of the presentation: What nuts & seeds should I roast? And what are the rough time and temperature parameters for each? (Remember, you have to verify these things for yourself, and take copious notes on what works.)

I have a “short list” of seeds & nuts I’ve already worked with. First the seeds:

  • Raw sunflower seeds (shelled)

  • Raw pumpkin seeds (either shelled or in-shell)

  • Roasted and salted squash seeds (in-shell)

  • Fenugreek seeds (raw, of course)

  • Raw sesame seeds

  • Fennel seeds (raw)

  • Anise seeds (raw)

  • Cumin seeds (raw, of course)

  • Raw flax seeds

  • Green coriander seeds

I haven’t tried these yet, but you can buy raw chia seeds and roast them.

And you can also consider sites like trueleafmarket.com to have a look at their heirloom seed collections. I can’t guarantee you that all of the seeds listed are edible and/or suitable for roasting, but if you buy a collection, you can always sprout and plant the ones that aren’t edible or suitable for roasting. Your yard will be happy...

These are the nuts I’ve worked with thus far (not necessarily all of them in my roasting activities):

  • Pistachios (both raw and already roasted)

  • Almonds (both raw and already roasted)

  • Pecans (both raw and already roasted)

  • Hazelnuts (I forget, but probably already roasted)

  • Walnuts (probably both raw and already roasted)

  • Macadamia nuts (however they come; probably already roasted)

  • Cashews (both raw and already roasted)

The nuts listed above I used to buy primarily at our local CVS, until they closed recently because of excessive theft.

But I’ve managed to find some pretty good deals at our local Lucky's, including pine nuts, which I haven’t yet tried.

In the case of the seeds, you can pretty much split them up into two categories: the seeds that are primarily in the herbs & spices category, and the rest of them, which are mainly vegetable seeds (although there might be some fruit seeds that are edible and/or suitable for roasting). It should be obvious which seed is in which category, in the list of seeds above.

For the vegetable-type seeds (sunflower, pumpkin, and squash), for air-roasting, the basic rule is to do five-minute increments at about 225-250°F, tasting after each increment and then waiting a while before the next session. If you include add-ons later on, be careful not to over-roast before adding any extra ingredients. And always monitor the results as you go, adjusting the temperature as necessary. —Actually, for the vegetable-type seeds, it’s prudent to try about 225°F at first. Depends on the seed type. The sunflower seeds, for example, can end up being partially browned, partially light. The flavor isn’t compromised; it’s just a bit different than sunflower seeds that are more uniformly a light brown.

For all the other herb/spice seeds, you should start at a temperature of about 200°F when you do your initial testing. Most of these seeds probably won’t do all that well above about 225°F, unless you prefer them browned to a significant degree, for whatever reason. And most of these seeds will probably not take more than about one or two five-minute increments, unless you lower the initial temperature to about 175°F. So, for the smaller, more delicate seeds, if you want to do add-ons after first dry-roasting them, you should probably start at that lower temperature.

Most of the nuts I’ve worked with can probably take a few five-minute increments at around 250°F, but for the less dense, more delicate varieties, you might consider starting at 225°F.

This next caveat may or may not apply to the seeds, but it's true for at least some of the nuts. If you add certain liquids such as the fermented sauces, or possibly even oils, to your roasting experiments, you may consider raising the temperature by 10-25°F once you've added the liquid.

If you get the time and temperature facets of the roasting just about right for the seeds that aren’t from fruits or vegetables, you will note that they have pretty different characteristics, as regards flavor, texture, and, well... The crunchiness factor.

Two of the crunchiest, in my estimation, are the fenugreek and cumin seeds, with flax being a close third. So if you want to add a somewhat recognizable flavor to a favorite dish of yours, but you’d also like to add that irresistible “crunch” factor, the three just mentioned are top-notch candidates for that job. They all have quite different flavor profiles.

Cumin is a staple in quite a few cuisines, and it tends to add a hearty, even somewhat meaty flavor to your dish. If you add roasted cumin seeds instead of the usual cumin powder, you get the flavor (with the roasting bonus!) plus the extra pleasure of that inestimable crunch that is sure to drive your millions of worldwide followers nuts.

Fenugreek has a more bitter tinge to it, while flax, naturally, tastes most like one of those grains you might use in baking bread.

Sesame is one of the most delicate, along with perhaps green coriander and anise. You would be best off starting with lower temperatures for all three of these, starting at around 175°F. All of these tend to brown pretty quickly.

But sesame is kind of special. Roasted (or toasted) sesame, either on its own or as the main ingredient—perhaps with water and/or olive oil to help smoothen it—is the heart and soul of tahini, which in turn, along with its sister ingredient garbanzo beans, is the heart and soul of everyone's beloved hummus.

I’m not Dr. Tahini yet—give me a minute—but I’d certainly love to be able to add that kind of positive notoriety to the bucket list of my dazed and confused resume!

However, what I can truthfully testify is that once you roast sesame seeds just so, and chew on them a bit, you’ll start getting that very real tahini flavor and mouthfeel. Yes: You yourself have to do the chewing, but that flavor and that mouthfeel are the very essence of tahini! (Now I just have to figure out how to get there from here—how to tahinify it, so to speak.) But don’t in the words of that infamous one, misunderestimate me! I’ve got it covered... Eventually. You just watch. Stay tuned.

Green coriander seeds, roasted: I can’t quite figure them out, and I’m sure they feel the same way about me. I've often used ground coriander as part of a five-spice mix in my baking, so the taste sensation is definitely familiar to me. But I just can’t quite place where these roasted seeds fit, exactly, within the culinary universe. Maybe they’re more of a kind of all-purpose type of roasted seed. After all, in my five-spice mix, they’re the flavor that's mostly in a kind of neutral territory, neither sweet nor having the “bite” of powdered ginger. Actually, roasted coriander seeds are kind of flax-like.

The ground coriander that’s typically available looks to be a rather light-brown color. If you overdo the temperature setting when you do your own roasting, it can easily become more of a dark brown. But they’re still good.

This brings us to the final pair, the licorice twins. Yes, Anise is more sensitive than her twin Fennel. Apparently she browns more easily. But both are sweet, as we know. And equally delectable, each in her own way.

Yet, if you yourself try these air-roasting experiments, you may well end up concurring with me that Anise is the midway point in the epic journey from Cumin to Fennel. They all add flavor, substance, and depth to the adventure, each in their own ways.

The herb/spice contingent of the seeds we’ve covered are the most difficult to handle in roasting because of their small size and delicate disposition. Accordingly, some of the add-on ingredients are a bit more difficult to add to those seeds, one of the primary ones being butter. For the smallest seeds, it’s probably best to add melted butter once you start adding extra ingredients. This makes it much easier to spread the love around!

For the larger seeds and pretty much all of the nuts, it’s pretty straightforward to add your additional ingredients, so I won’t dwell on that. You go ahead and do the experiments that you’re drawn to. And have lots of fun.

The last thing I want to mention for now is that it might be interesting to put together a potentially very tasty roasted seed mix.

The key to such an idea is to get the proportions of the various seed types dialed in so that the various flavors will complement and enhance each other. A first useful experiment would be to dry-roast all of the seed types—except perhaps the in-shell squash seeds, which might be best fried in butter—and then to mix roughly equal parts of the sunflower, pumpkin, and in-shell squash seeds with considerably smaller amounts of all of the rest of the seed types, with the stronger flavors in smaller proportions than the others.

This concludes this episode of seed & nut roasting. Happy roasting, and buy those awesome cookbooks! Peace.

Except: There’s a P.S., courtesy of the newly inaugurated Dr. Bob’s Test Kitchen. This just in! Breaking news:

Wow! What a completely awesome roasted seed mix!

It has, for the image above, the following:

  • 0.5 oz butter-fried, in-shell pumpkin seeds

  • 0.5 oz butter-fried, in-shell squash seeds

  • 1.0 oz air-roasted pumpkin seeds, no shell

  • 1.0 oz air-roasted sunflower seeds, no shell

And a pinch of each of the following air-roasted seeds:

  • Fenugreek

  • Cumin

  • Fennel

  • Anise

  • Flax

  • (Green) coriander

  • Sesame (about half air-roasted in butter)

I wanted to start with a small amount, to see if I could get the mix more or less right, and I think I pretty much nailed it!

The in-shell seeds add a bit of the buttery and salty taste; you know what the pumpkin and sunflower seeds add; and the rest of the seeds provide the rest of the excellent flavoring.

It seems that the main seed to be careful with, quantity-wise, is the coriander.

As for the other “herb & spice” seeds, sesame is of course great, and that amount can be tuned upward.

Fennel and/or anise can be heightened if you want a more licorice-forward taste.

Cumin is in pretty much the same league as the previous three; you could do equal amounts of each and it would still be fine. You could probably put flax in the same boat as cumin.

Fenugreek is borderline, nearly in the same league as the others, but it has a slightly stronger flavor, so it should probably be used more sparingly.

And coriander should in most cases be downplayed, unless you prefer quite a bit of that flavor. On the other hand, if it were air-roasted in butter with perhaps a few of the “sweet” herbs or spices, such as dried basil, marjoram, cinnamon, nutmeg, maybe even ginger, that might help it out. ...Update: I tried this using melted butter and the rest of the ingredients mentioned, tasted it, and then added a small amount of sweetener (blue agave nectar, in this case—you could also use either maple syrup or honey), and it does help mellow it out.

But the main thing to keep in mind with these “herb & spice” seeds is to try to ensure that none of them drowns out the others. That’s why it's so important to taste them individually, so that you can carefully observe their flavor, texture, and crunchiness factors.

Bon appétit!