This rather long, snakelike fish-of which there are both freshwater and saltwater varieties-has a smooth, scaleless skin. Before cooking, the thick, tough skin and outer layer of fat must be removed-a task usually handled by the fish dealer. Fresh eel should be refrigerated and used within a day or two. It's excellent baked, stewed or grilled. Because conger eel meat is very tough, it is most often used in soups and stews. Eel is also available jellied in cans or smoked. Though considered a fatty fish, the eel is high in vitamins A and D, as well as being a good source of protein.