The versatile leek belongs to the allium family and is a mild cousin to onions and garlic. Rather than forming a bulb like onions, the leek put all its mo-jo into the stem. The white part is best, but how far into the green you slice is a personal matter - where it still holds together is recommended. Leeks are a great foundation to soups. Use the leek’s white and very light green parts for soups, quiches, tarts, risottos, and pastas, or for sautéing, braising, roasting, or grilling.