Foie gras (/fwɑːˈɡrɑː/; French: [fwa ɡʁɑ]); French for "fat liver") is a food product made of the liver of a duck or goose that has been specially fattened. By French law, foie gras is defined as the liver of a duck fattened by gavage (force-feeding corn), although outside of France it is occasionally produced using natural feeding. A pastry containing pâté de foie gras and bacon, or pâté de foie gras tout court, was formerly known as "Strasbourg pie" (or "Strasburg pie") in English on account of that city's being a major producer of foie gras.
Foie gras is a popular and well-known delicacy in French cuisine. 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 (the lowest quality), and may also be served as an accompaniment to another food item, such as steak. French law states that "Foie gras belongs to the protected cultural and gastronomical heritage of France."
The technique of gavage dates as far back as 2500 BC, when the ancient Egyptians began keeping birds for food and deliberately fattened the birds through force-feeding. Today, France is by far the largest producer and consumer of foie gras, though it is produced and consumed worldwide, particularly in other European nations, the United States, and China.
Gavage-based foie gras production is controversial due to the force feeding procedure used. A number of countries and other jurisdictions have laws against force feeding or the sale of foie gras.