Exploring 7 Types of Onions and Their Culinary Uses

The humble onion is as indispensable to the culinary arts as butter or eggs—or for that matter, knives or plates.

It's rare for a food to be sweet, savory, pungent, and aromatic all at once, but that's exactly what onions achieve. In a real sense, onions elevate food from mere sustenance to something truly enjoyable, enhancing flavor and making it taste great.

Onions don't offer much in terms of nutrition. They contain some vitamins and minerals, but these are found in greater abundance in other foods like rice or broccoli. Additionally, onions aren't necessary for a recipe's success, but if you removed them, the dish wouldn't taste as good.

A Culinary Luxury

Thus, onions are a luxury, yet these small, brown, sulfurous orbs are cheap and plentiful and will grow just about anywhere, as evidenced by the fact that every style of cooking on earth features them.

Onions can be roasted, grilled, pickled, caramelized, battered and deep-fried, sliced thinly or chopped and served raw in salads, sandwiches, dips, or as a garnish for tacos, making them among the most versatile and ubiquitous ingredients in the culinary arts.

Onions make up a third of the classic mirepoix, a basic mixture of onions, carrots, and celery used to enhance the flavor of soups, stocks, and sauces, appearing under different names in different cuisines, such as the Italian soffritto, or the so-called "holy trinity" of Cajun cooking (which substitutes bell peppers for the carrots).

Onions are part of the genus Allium, and they're related to garlic, chives, shallots, and leeks. Both the bulb and the shoots are edible. Slicing onions releases a sulfur-based vapor that irritates the eyes.

China produces more onions than any other country, but with a population of 1.3 billion, they consume most of what they grow. Interestingly, the world's top onion exporter is the Netherlands.

Yellow Onions

The workhorse, the staple, the everyday brown beauty, yellow onions are suitable for any conceivable use, other than perhaps as a garnish for your martini (use a pearl onion for that). You could easily live a rich and fulfilling life even if this were the only onion you ever tasted.

Its heavy brown parchment skin surrounds ivory white flesh with a strong, sulphury, pungent flavor and aroma. If a recipe says onion without specifying what type, it's assumed to be a yellow onion. Use them for making French onion soup or a batch of classic caramelized onions.

Sweet Onions

Larger and slightly flatter than yellow onions, sweet onions have lighter-colored, less opaque skin and contain more sugar, making them excellent for caramelizing. Their larger size and sweeter flavor make them ideal for onion rings. Varieties include Walla Walla, Maui, Vidalia, and others labeled "sweet."

White Onions

White onions have a papery white skin and a milder, sweeter flavor than yellow onions, making them perfect for serving raw in fresh salsa or homemade guacamole.

Red Onions

Sweet and mild enough to be eaten raw, both the exterior skin and the flesh of red onions are a deep magenta color, which makes them particularly good additions to salads or anywhere else a splash of color will enhance the appearance of the dish. I love to use red onions in salads and on sandwiches and burgers.

Shallots

Shallots are small, brown-skinned onions with purplish flesh, and their bulbs are composed of multiple lobes, similar to how garlic bulbs are divided into individual cloves.

Pungent and garlicky, shallots are somewhat unappreciated in the United States—at least based on how infrequently they appear in recipes, and the careless disarray with which they tend to be displayed at the supermarket.

Which is a shame, because shallots are possibly the most sublime onion. They impart a very intense flavor, and because they're smaller, composed of thinner layers, they can be minced very finely and used in salad dressings and sauces. They're lovely to roast, however; peel and halve them, and toss them in the bottom of the pan when you're roasting a chicken.

Green Onions

Green onions are immature onions that haven't fully formed a bulb, or only partially. The entire plant is typically used, including the tall green shoots, and they make a wonderful garnish for soups, omelets, and tacos, adding both color and crunch. They go by other names, including scallions, spring onions, cebollitas (in Spanish), salad onions, and even—shallots!

That's right, in some countries in which English is spoken, green onions are referred to as shallots, sometimes "French shallots," to avoid further confusion. The differences in how we refer to culinary items and ingredients is wide even if the same language is used. However, green onions, shallots or cebollitas can be easily recognized by their aspect and taste, regardless of their name.

Leeks

Leeks are a truly marvelous vegetable, and also sadly underappreciated. Shaped like overgrown scallions, leeks are lovely in soups and sauces, and one of our favorite ways to prepare them is à la gratinée—baked and topped with seasoned breadcrumbs and Gruyère cheese. Baking the leeks mellows their flavor and softens them.