Although the literal translation from French is "fat liver," foie gras is the term generally used for goose liver. This specialty of Alsace and Perigord, is in fact, the enlarged liver from a goose or duck that has been force-fed and fattened over a period of 4 to 5 months. These specially bred fowl are not permitted to exercise — which, combined with the overeating, creates a huge (up to 3 pounds), fatty liver. After the bird is killed, the liver is soaked overnight in milk, water or port. It's drained, then marinated in a mixture usually consisting of armagnac, port or madeira and various seasonings. The livers are then cooked, usually by baking. The preparation, of course, depends on the cook. In general, goose liver is considered superior to duck liver; all foie gras is very expensive. At its best, it is a delicate rosy color with mottlings of beige. The flavor is extraordinarily rich and the texture silky smooth. Pâté de foie gras is pureed goose liver (by law, 80 percent) that usually contains other foods such as pork liver, truffles and eggs. Mousse or puree de foie gras must contain at least 55 percent goose liver. Foie gras should be served chilled with thin, buttered toast slices. A sauternes is the perfect accompaniment.