Store in the vegetable drawer of the refrigerator. Looseleaf green such as spinach, arugula and dandelion may be sauteed in a small amount of oil, steamed in the water that clings to their leaves after cleaning, or blanched in a large quantity of boiling water. With any of these methods, cook only until the greens wilt. Heads of sturdier radicchio and Belgian endive can be grilled or roasted, and the leaves, whole or chopped, can be braised in a small amount of liquid. Because of their assertive flavors, greens are often combined with milder foods, such as pasta or potatoes.
Cooked greens are also good chopped and mixed into omelets, pasta fillings and sauces.
Spinach is an excellent source of folate and beta carotene, and it contains iron and calcium as well, though the oxalic acid in the leaves interferes with the absorption of these minerals. Greens are also high in phytochemicals, which may help protect against cancer and heart disease.