Some people say there’s no such thing as unappetizing chocolate, but contemporary artists beg to differ. Dieter Roth deliberately let his molded-chocolate sculptures grow stale and crusty (Chocolate Lion, 1971). Ed Ruscha wallpapered Chocolate Room (1970) with silk-screened chocolate, and kept it fresh with reinstallations. For 1992’s Chocolate Gnaw, Janine Antoni chewed away at a 500-pound hunk of the stuff—yummier than the scatological body art of Paul McCarthy and Karen Finley, but not quite as tempting as Vik Muniz’s wonderfully goopy drawings with chocolate syrup (one of his “Pictures of Chocolate,” 1997).