Aromatics for soup are like a bass player for a band. When you listen to music, you almost never pay attention to the bass. But when it’s missing, you notice right away.
Aromatics are the same. Without them, your soup will be boring, regardless of how well you made it.
Well, it depends on who you ask. My definition of aromatics is food (edible or inedible parts) that release flavor when sauteed or sweated in oil or fat. This then infuses your soup--or whatever you’re cooking--with that same flavor.
In my experience, most aromatics are plants, but not all plants are aromatics. Here are a few.
Alliums are a group of related vegetables that include onions, leeks, and shallots. These three have similar but not identical flavors, so it’s best to pick just one. Leeks are generally milder, while shallots can pack a bit of a wallop.
Scallions and chives much milder in flavor, and make great aromatics for soup, especially lighter soups.
Garlic, while related, is in a class by itself. Too much, and it will overpower everything else; used in moderation, and it enhances almost any other aromatic. Just be sure to add it to the pot after all the other aromatics have had a chance to cook, as garlic can burn quickly.
Peppers of all kinds are great aromatics for soup. Bell peppers (any color) impart a light, fruity, almost sweet taste, while other types of peppers can also add spicy heat. Anaheims and poblanos are the mildest of these, with banana peppers being a step up.
If you want even more heat, you can try jalapenos, or even serranos, but anything hotter than these are not very good in soups. Since soup is liquid, the heat will reach every part of your mouth, which is not a comfortable experience. Save the hotter chilies for sauces and stews.
Another option with peppers is the smoked varieties. Smoked poblanos (also called “ancho”) and jalapenos (“chipotle”) have all the heat of their fresh variants, but add a nice, earthy, smokey flavor. It should be noted, however, that these are not usually sauteed. Instead, they are usually added to the soup after the broth.
Lastly, dried chili flakes are another great way of imparting both heat and pepper flavor to your aromatic mix.
Onions and their relatives are not the only root vegetables that count as aromatics. Carrots are the classic example, but turnips, rutabagas, and parsnips all work just as well. All of them impart a sweet flavor to dishes, which is not surprising since the main purpose of these large roots is to store sugar as fuel for the plant.
Another root vegetable that’s often overlooked is celeriac, or celery root. While not truly a root of the plant that we know as celery today, it is related, and has a similar flavor.
While not a root strictly speaking, ginger is a rhizome that packs a powerful culinary punch. It is both fragrant and pungent, and pairs well with both sweet and savory flavors, making it a versatile ingredient in many cuisines, especially Asian ones. Galangal, its lesser-known cousin, has a more citrusy, even peppery taste.
Another potent rhizome is turmeric. You may be familiar with it in its powder form, which is often used in pickles and mustards to add both a deep, earthy taste as well as a distinctive yellow hue. But fresh turmeric is excellent as part of a base for curries and middle eastern stews. Just be careful when peeling, as they will temporarily stain almost anything they touch.
When we think of where plants concentrate their nutrients (and therefore flavor), we don’t often think of the stalk. But the stalk is the main conduit between the roots and the leaves, flowers, and other visible parts of the plant. This can result in a “traffic jam” of taste, making them very versatile aromatics for soup.
Celery is clearly the most obvious example, and its savory flavor is indispensable in many Western cuisines.
A worthy replacement for celery is fennel root, also known as anise. Visually, it looks like a cross between celery and an onion, and its flavor is very similar to that of celery, but with a strong hint of licorice.
Asian cuisines have their own representative in lemongrass, which adds a distinctive grassy, citrusy flavor to curries and other foods.
While fresh herbs are certainly aromatic, their leaves tend to be too delicate to be cooked in oil or fat, and are best used for finishing a dish rather than starting one. The same is not true for herb stems, however, and you can make good use of stems from all manner of herbs, like basil, parsley, cilantro, etc.
Some leaves are tough enough to withstand lengthy sauteing. In Western cooking, bay leaves are a staple, while once again Asian cuisine has its counterpart in curry leaves. I’m not a big fan of using either, however, as I don’t like having to fish them out before serving. Even worse is leaving them in and having someone choke on one.
Powdered spices are great aromatics, so much so that they barely need mentioning. In fact, I won’t bother listing them here, as I plan to make another page specifically about spices. However, I do want to call out some whole spices, as they offer an opportunity for a deeper, richer flavor when combined with other aromatics.
Seeds are the most common whole spice, including fennel/anise seed, coriander seed, and fenugreek.
Peppercorns are not seeds, but rather the fruit of the pepper plant, and both its black and green whole forms make an excellent addition to any aromatic combination.
One trick you can try with seeds of almost any sort is to roast them ahead of time, either by gently toasting them in a dry pan over medium heat, or in the oven for a few minutes at about 350 degrees F. This adds a kind of nutty dimension to their flavors, which can work wonders in your dishes.
Seed pods can be used as well, cardamom and star anise being the two most common examples. I find star anise to be particularly useful, as it creates flavor enhancing compounds when sauteed with caramelized onions. These compounds are absolutely magical when added to a braised meat dish or sauce. Seed pods should be removed before serving. This is best done once the aromatics are fully cooked.
Whole cloves are dried flower buds that add a massive amount of flavor to any dish. In fact, they are so powerful that you need to be a little careful when using them, as they can be mildly toxic in large quantities. Oil from cloves has even been used as a numbing agent for centuries. Again, they should be removed before eating.
Last, but not least, cinnamon sticks are the dried bark of various trees. They are perfect for middle eastern and north African dishes. Again, the warning to remove before eating applies.
Whole fruits don’t lend themselves well to the idea of aromatics, because they evolved to taste good as they are, rather than having concentrated flavors. The exception to this is citrus zest (the colored skin layer, NOT the white rind), which contains oils with high concentrations of aromatic compounds.
If you peel away the zest from an orange or lemon, you’ll be rewarded with a blast of refreshing scent reminiscent of cleaners, but without the harsh chemical smell. You can add the zest (either by peeling or grating) to other aromatics to add delicious fruity notes to your dish.
I mentioned above that most aromatics are plants. While meat in its basic form will never be an aromatic product, some processed meat can be.
Bacon, pancetta, and cured ham all have distinctive flavors that can be released through the saute method.
Sausages work as an aromatic as well. Like bacon and other cured meats, sausages contain both meat and fat, but they usually also include spices, which is what makes them so tasty in the first place. Almost any type of sausage will work.
Meat products work best when cut into small pieces and sauteed at a lower temperature. Rather than heated oil coaxing aromatic compounds out of plant cells, extracting flavor from meat products is actually just a matter of rendering fat which already has flavor in it. Once the fat is rendered, the remaining solids can start to caramelize, which adds even more flavor.
Another exception to the “all plants” rule is seafood shells, like shrimp and lobster, which can be used to make broths and bisques.
There’s no right or wrong way to combine aromatics. In the end, it all comes down to what you and your family enjoy. But if you want a few tips, check out my page on aromatic combinations.