Endive produces"heads" that fall somewhere between the compactness of iceberg lettuce and the openness of a looseleaf type. For the best flavor, mild days and cool nights are the ideal. There are two types: the frilly curled Endive with pointy leaves, and a smoother-leafed Escarole. Endive has a slightly bitter, buttery taste. It is very popular, and attractive in salads and is also used in soups and stuffings.