Leeks deserve more attention than they get, and I think so for a few reasons. For starters, they’re useful in so many dishes—in the same league as carrots, onions, and celery, and they make a great base for delicious stuffings, stews, soups, and sautés.
But a leek’s unique combination of silky texture and herbal-sweet flavors can take center stage, too. A leek can stand up to bold flavors, becoming a delicious vegetable in its own right. Give leeks a try this way and I guarantee you’ll welcome this sweet and versatile vegetable into your repertoire.
A leek is like an onion, but greener-tasting
The flavor of a leek is like onion but more herbaceous, though not like any herb in particular, and in fact it marries well with nearly all herbs. But while onions add a single-edged sweetness, leeks add both sweetness and vegetable flavor. This is why they give depth and complexity and why, as a stand-alone vegetable, they’re especially interesting and flavorful.
Leeks are often associated with spring: That’s when small, young ones first start to show up at market. But in climates like the Pacific Northwest, where it’s not too hot and not too cold, leeks are farmed commercially almost year-round; this is why they’re available around the country most of the year, though regions and climates will vary. Leeks that have over-wintered or have been exposed to a lot of cold in the field can have a whitish, fibrous seed stalk running down the center, which you’ll want to discard.
At the market, look for firm, green leeks with the roots still attached; pass on any that are limp, pale, or withered. Fresh leeks will keep in the refrigerator for up to a week wrapped loosely in a damp towel.
You’ll use the bottom white part and a bit of the light green. A leek’s dark green leaves are generally too tough for eating, but they’re a flavorful addition to any stock. Large and medium-size leeks are what you’ll most often find at market. But if you see small, tender baby leeks, grab them. You can use just about the entire stalk, and they’re wonderful grilled and in stirfries, vegetable sautés, and salads.
You’ll need to wash leeks carefully. They grow in sandy soil that’s mounded up around them, which is how most of the stalk stays white. Grit nestles easily between the many leaf sheaves, so thorough cleaning is always required (see below). This only takes a few minutes, but it’s a must so that the silky pleasures of your perfectly prepared leeks won’t be marred by a mouthful of grit.
Leeks can handle bold flavors
You’ll often see leeks paired with rich ingredients, like cheese and heavy cream in potato gratins, leek and potato soups, and creamy pasta dishes. While I love those combinations and have included some in the recipes, I’m particularly fond of pairing leeks with bold, assertive flavors.
Resinous herbs like thyme and sage are delicious with leeks; the Salmon Fillets with Herbed Leeks gets a healthy dose of these herbs. A good amount of garlic is great with leeks, too. You’d think this would be gilding the lily, so to speak, but surprisingly, it isn’t. In my soup recipe, several cloves of garlic simmer with the leeks; they bolster rather than overpower the leek’s flavors. And a robust roasted pepper vinaigrette is a great way to sauce the grilled leeks. A mustard vinaigrette with capers and fresh herbs is also delicious on grilled leeks.
Thorough cooking turns leeks velvety
While garlic, scallions, and onions can be tossed into a dish raw, leeks must always be cooked, and when grilled, they first need a short parcooking. And while some vegetables benefit from al dente cooking, leeks definitely aren’t one of them. Which isn’t to say that they should be cooked to death, but in order to get tender, velvety leeks, you must cook them until they’re soft or you’ll get a fibrous, indigestible result.
One thing to watch out for is sticking in the pan. Leeks contain sugars just like onions do, but they can be more prone to sticking because they contain less moisture. In the recipes where I’ve called for sautéing leeks uncovered, I’ve been sure to call for enough butter or olive oil to prevent any sticking or scorching problems. Another good way to avoid this is to cook sliced, rinsed leeks with droplets of water still clinging to them and just a little bit of fat in the pan, as in the salmon recipe.