Foie gras, the fattened liver of a duck or goose, has become a controversial food, even for meat eaters, because of the way it is produced.

With rare exceptions, foie gras production involves a process called gavage—the French term for the force-feeding of ducks or geese through a tube that is inserted into the birds’ mouths and down the esophagus. The result is the fattening of the birds’ livers that gives foie gras its distinctive flavor.

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