A vegetable in the onion family, leeks (Allium Porrum) are similar in appearance to scallions. They are long and cylindrical in shape with white stems at the root end and stiff green or blue-green leaves toward the top.
With a subtly sweet and earthy flavor, leeks can be eaten raw or cooked. They are frequently used to flavor quiches, casseroles, stews and soups like the classic vichyssoise.
Leeks are thought to be native to Europe and Asia where they have been cultivated for more than 3,000 years. In 640 A.D., Welsh combatants wore leeks in their hats to distinguish themselves from the enemy Saxons. Leeks remain a symbol of pride in Wales where St. David's Day is annually celebrated with a traditional meal of leek broth.
Leeks are available year-round in most markets, but they are most plentiful from September through the end of April.
Look for younger leeks (these have a more delicate flavor and texture) that are slim and small to medium in size. They should have clean, white, straight bulbs and firm, tightly rolled, fresh green tops. Avoid wider, over-mature leeks with blemished leaves or rounded bulbs as these are sure to be tough and woody.
Fresh leeks will keep in the refrigerator for up to seven days if stored properly. Because their aroma can be absorbed by other foods, wrap leeks in plastic and keep them in your vegetable drawer.
Cooked leeks should be covered, refrigerated and consumed within one to two days.
Since leeks are grown in sandy soil, they need to be thoroughly cleaned before eating. Remove any withered outer leaves, then trim the darkest portion of the green tops and the rootlets at the base.
- If cooking leeks whole: cut a slit about one inch below where the leaves start to turn green and slice toward the top end (this keeps the stem in tact). Unroll the leaves and wash under cool running water.
- If cooking leeks sliced: begin cutting down the center of the stem at the bulb end. Chop as desired and place the leeks in a bowl of lukewarm water. Swish the leeks around and scoop them out. The dirt will settle at the bottom of the bowl.
Once cleaned, leeks can be added raw to salads or braised, steamed, stir-fried or microwaved for a delicious side dish. Since leeks tend to overcook quickly, cook them until just barely tender. They're done when you can pierce the base with the point of a sharp knife.
In general, leeks can be used as a substitute flavoring for onions in most recipes.
Onions should not be used in place of leeks, however, as they have a much stronger flavor which will alter the outcome of your dish.