Escarole is green chicory with just a hint of bitter flavor. It forms a broad, open head that resembles leaf lettuce. Wash well, taking special care to go over the base of the inner leaves with your fingers where soil often clings. Use the tender inner leaves to enliven mixed salads. Prepare its outer leaves with sautéed onion and garlic, adding escarole to the pan once alliums are tender; cooking until leaves are just wilted and turn dark. Salt and pepper to taste.