A pudding basin is a deep, heatproof bowl designed for cooking steamed puddings, the classic example being the Christmas pudding. Traditionally made of earthenware and now commonly of heatproof plastic or ceramic, it has straight or slightly sloping sides and a wide rim that takes a pleated cover of greaseproof paper or foil, tied down with string to keep steam and water out during the long steaming. The basin’s shape gives the pudding its familiar dome when turned out, and its sturdy walls conduct the gentle, even heat that transforms a raw mixture of fruit, suet, and crumbs into a dark, rich pudding over several hours. Basins come in graduated sizes, from individual portions to family puddings serving a dozen.