The invention relates to an appliance for cooking food under pressure. The appliance includes a vessel and a lid for locking relative to the vessel to cooperate therewith to form a cooking enclosure suitable for rising in pressure. The appliance also includes bayonet locking means forming first and second series of projections that are secured respectively to the shell of the lid and to the shell of the vessel which cooperate with one another to lock the lid to the vessel. Each projection of at least one of said series is adjacent to a respective opening formed through the corresponding shell.