14 Avenue is a reliable mid-range bistro on the main shopping street, a couple of blocks back from the casino. The menu changes with the season and the boats — expect grilled bar with fennel, oysters and a glass of Muscadet, fish soup, and the occasional Breton-influenced dish like cotriade (a humble Breton bouillabaisse).
Smart but not formal, indoor and pavement seating, around €30-45 for a serious lunch. They take credit cards and bookings; the wine list leans Loire and very fair.