Crème anglaise is an example of a stirred custard and is the classic French dessert sauce. It is also used as the base for ice creams, pots de crème, and Bavarian creams (richly flavored custard with the addition of whipped cream and gelatin).
When making a stirred custard, the objective is to thicken it by gently poaching the egg yolk and sugar mixture in hot milk without allowing it to form a solid mass. To achieve this, during the cooking process the custard must be kept in constant motion by stirring with a wooden spatula in a Z or figure-8 pattern. This ensures that the protein of the yolks coagulates evenly, with no lumps.