A bottomless band of stainless steel, round or square and usually 4 to 8 cm tall, used to shape layered desserts that are assembled rather than baked in a tin. Mousse cakes, entremets, cheesecakes with a biscuit base and layered sponge-and-cream cakes are built inside the ring on a tray or cake board, chilled until set and then released by warming the ring briefly or sliding a knife around the edge. The result has perfectly straight sides.
Rings also serve as moulds for tarts baked directly on a lined tray, and smaller ones plate individual portions of rice, salad or tartare. Lining the inside with an acetate strip gives a glossy edge on a set dessert and makes the release cleaner.