Traditional foie gras comes from the liver of a goose or a duck, in fact the name means 'fat liver'. To give the foie gras its special flavour, in the traditional method the birds are kept in close confinement and force-fed, usually through a tube or funnel, until the bird gains a lot of weight and the liver gets engorged.

The practice is a very old one going back as far as Ancient Egypt. In France there is a long history of using ducks and geese (these birds are chosen because, as migrating birds, they have evolved to gain weight quickly and eat a wide variety of foods), and gavage or force feeding is quite a complicated procedure taking many weeks.

However, in modern times many producers use different methods to make them less cruel, though many animal rights supporters think the practice should be banned altogether and some restaurants refuse to serve foie gras.