Hyrtox, a kelubar gehreleth summoned to Gehenna by accident, opened a restaurant in the middle of nowhere, offering food for hefty prices. Everything he serves is disgusting, but eatable, like the mud cake with fruits or the eye salad, and nutritious for those suffering from the hunger that assaults the plane. Anyone who talks bad once about the yugoloths gets a free meal and those that get him a 'loth corpse get provisions for a week.
See two things, then there's a third one hidden. See four things, then the fourth's a lie. See three things, and you're in luck (unless it's three angry baatezu).