Onions are an essential ingredient for building flavor in almost every savory dish, but do you ever get confused about which one to use? There’s a reason grocery stores offer so many different types of onions, and I’m here to demystify the differences between several common types of onions. Learn more about common onion varieties and how to use them in your kitchen.
Whenever you need an onion, you’ll likely find an overwhelming number of varieties in your grocery store. Feeling bewildered? No need to cry, at least until the chopping begins! Let’s take a look.
Types of Onions
If a recipe isn’t clear on which type of onion to use, reach for a yellow onion. These are the most common option you’ll find at grocery stores, and these are the best option for cooked when you want a balanced flavor.
Ranging in size from golf ball to softball, yellow onions have a round shape and papery skin. These all-purpose onions are especially great for long, slow cooking; they develop a rich, pleasantly sweet flavor when caramelized or added to soups and stews. However, I’d avoid using them raw due to their strong flavor before cooking.
When to use: Cooking, caramelizing, soups, stews and casseroles (see my full list of recipes using yellow onions)
Named for its thin, bright white skin, the white onion has a cleaner, milder flavor than its yellow counterpart. Thanks to their pleasant taste and crisp texture, white onions are a popular pick for eating raw; you’ll often find them sliced into rounds on burgers or diced finely as a topping for Latin American cuisine.
Compared with yellow onions, white onions have a sharper, more pungent flavor. They’re also usually more tender, and they have a thinner, more papery skin.
When to use: As a substitution yellow onions, or finely shaved or diced to serve raw along with other ingredients (pico de gallo, etc.)
Also known as fresh or summer onions, the sweet onion has an especially mild flavor thanks to a low concentration of pyruvic acid (the pungent stuff that makes you tear up!). Sweet onions are delicious served raw on burgers, in salads and relishes, and they’re best enjoyed during their growing season, which extends from April to September.
From a distance, they look similar to yellow onions, but with a flatter shape. You might see these squat, pale yellow onions sold under the names of popular varieties like Walla Walla, Bermuda, Maui, or vidalia (more on these below).
When to use: when you need a mild, raw topping with crunch (hamburgers, sandwiches, etc)
Vidalias are a specific variety of sweet onion that originated in Vidalia, Georgia. Today, this name may only be used for sweet onions grown in a defined geographic region that spreads across all or part of twenty Georgia counties. The state vegetable of Georgia, Vidalia onions get their mild flavor thanks to the low sulfur content of the region’s soil.
When to use: interchangeably with any sweet onion variety (see above)
It’s easy to spot these onions in the supermarket; they’re immediately recognizable thanks to their deep purple skin. Red onions have a bold, sharp flavor that some people find too assertive; others, however, love adding a few slices of raw red onion to sandwiches, tacos, dips, or salad for a spicy punch.
Though they’re typically served raw, red onions are also delicious when grilled, roasted, or pickled. Seasonality strongly affects the flavor of these colorful onions; they’re sweeter from March through September, and spicier during the winter months.
When to use: raw on sandwiches, tacos, dips, or salad when you want a spicy punch. Also good for grilling, roasting, and pickling (see my full list of recipes using red onions)
When you first spot shallots at the store, you might think they’re just smaller red onions with an unusual, slightly oblong silhouette. In truth, they’re a variety all their own. These clustered, bulb-shaped alliums have a wonderfully mild flavor profile with a hint of garlicky richness.
Shallots are an essential ingredient for many vinaigrettes; they’re also very popular in Asian and French cooking. (learn more about shallots)
When to use: as a milder substitute for red onions, in vinaigrettes (see my archive of recipes using shallots)
Scallions (Green Onions)
Scallions (aka green onions) are long, thin onions with a white base and hollow, dark green top; they’re usually sold in bunches at the grocery store. Sweet and mild, scallions offer a light onion flavor even when served raw.
They’re often chopped for use as a garnish, but they’re also delicious when grilled and served whole. Scallions are at their best from late spring through late summer. They’re more perishable than most other onion varieties, so make sure you plan to use them soon after you bring them home from the market. Scallions are a common ingredient in Asian cuisine. (learn more about scallions)
When to use: diced as a garnish, Asian recipes (see all of my recipes with scallions)
It’s easy to confuse spring onions with other types of onions like scallions or leeks; they both have white bottoms and tall green stalks. To confuse things even more: some countries besides the USA refer to green onions as spring onions. Here’s how to tell them apart: spring onions have a small bulb at the base, while scallions are completely straight.
That bulb appears because spring onions are actually yellow, white, or red onions that were pulled from the ground before they reached maturity. Spring onions are slightly spicier than scallions, though their flavor is still fairly mild. They become sweet and tender when grilled whole; they’re also perfect for pickling.
When to use: as a substitute for scallions, grilling, pickling, caramelizing
Leeks look like giant scallions, but they’re actually another distinctive onion variety! Bred to survive through the winter months, leeks are more sturdy and fibrous than scallions or spring onions.
Their white bases have an extremely sweet, mild flavor when cooked; they’re particularly great for braising, sautéing, or adding to soups. Though the woody tops of leeks aren’t great to eat, they’re perfect for adding flavor to homemade stocks.
Because of their fibrous texture, leeks generally aren’t eaten raw. Look for fresh leeks from late fall through early spring, and wash them thoroughly to remove any grit and sand from between their layers before cooking.
When to use: braising, caramelizing, soups (see my recipes with leeks)
Also called white cocktail onions, these petite onions are known for their exceptionally sweet and delicate flavor. You’ll sometimes see red pearl onions as well. Pearl onions can be creamed, roasted, or glazed; you’ve likely also spotted a peeled and pickled pearl onion as a cocktail garnish.
Peeling can be the most tedious part of cooking with pearl onions. You can buy frozen, pre-peeled pearl onions, or blanch them in hot water to help the skins slide off easily.
When to use: in stews (such as boeuf bourguignon), creaming, roasting, glazing, cocktail garnish
Slightly larger than pearl onions, cipollini onions are recognizable thanks to their flattened, disk-like shape and yellow hue. Because of their unusually high sugar content, they’re incredibly sweet when roasted, caramelized, or sautéed.
Like pearl onions, cipollinis can be a bit of a chore to peel. Try chopping off both ends with a sharp knife, and then using a paring knife to slice away the rest of the peel.
When to use: roasting, braising, caramelizing, sautéing (check out Cipollini Onions Braised in Red Wine on Food Network)
How to Chop An Onion
Want to learn my quick technique for chopping onions? Check out my chopped onion tutorial with step-by-step photos!