sentences:  Its flavor is described as rich, buttery, and delicate, unlike that of an ordinary duck or goose liver.Foie gras is sold whole, or is prepared into mousse, parfait, or pâté, and may also be served as an accompaniment to another food item, such as steak.The technique involves gavage, cramming food into the throat of domesticated ducks and geese, and dates as far back as 2500 BC, when the ancient Egyptians began keeping birds for food.