Leeks will not form bulbs or produce cloves like their cousins, but instead develop an edible, 6 - 10 inch-long, round stem that can measure 2 inches in diameter. The leek's cylindrical, white, edible root gradually becomes a stalk with a fan of dark green, flat leaves. Offering an earthy, mild onion flavor, the texture of a leek is crunchy when raw and silky when cooked. Leeks are considered to be the sweetest and most mild members of the onion family.
Though leeks are often interchangeable with onions and garlic, they can require specific preparation and are often highlighted in recipes for their particular flavor. Slowly cook sliced leeks in olive oil and butter until soft, then toss with beans and pasta. Cook with potatoes and vegetable broth, the puree for a classic potato-leek soup. Slow-cook with butter and cream and serve with seafood such as seared scallops. Grill whole or halved leeks and serve as a started or topping for bruschette. Braise in wine and vegetable stalk until very tender, then top with a mustard-based vinaigrette. Add sauteed leeks to quiche, savory tarts or pies. To store, refrigerate in a plastic bag up to three days.