Fois Gras
One of the most unpleasant foods (both morally and by taste), Fois Gras is considered a delicacy that few can afford, and even fewer can stomach. It is made from the liver of a force-fed duck or goose, and although it is sometimes described by conniseurs as "rich, buttery and delicate", it is perhaps telling that it is occassionally served in noble banquets and rarely anywhere else.
Vizier Victor Dargent-Laureat seems to have gotten it into his head that he should enjoy Fois Gras, even although he doesn't, and therefore keeps trying to acustom himself through exposure. His wife, Viziera Satine Dargent-Laureat, doesn't seem to mind the taste, but finds the preparation process a bit cruel.