Chocolate ganache is an emulsion of chocolate and heated cream, made by pouring hot cream over chopped chocolate and stirring until smooth. The ratio of chocolate to cream determines its use: more chocolate produces a firm mixture for truffles or cake fillings, while more cream produces a pourable ganache used as a glaze or sauce. Ganache is a staple of French pastry, used to fill eclairs and tarts and to coat cakes, and can be flavored with vanilla, coffee, liqueurs, or spices.