<Li> Media: Pie </Li> <P> A pie is a baked dish which is usually made of a pastry dough casing that covers or completely contains a filling of various sweet or savoury ingredients . </P> <P> Pies are defined by their crusts . A filled pie (also single - crust or bottom - crust), has pastry lining the baking dish, and the filling is placed on top of the pastry but left open . A top - crust pie has the filling in the bottom of the dish and is covered with a pastry or other covering before baking . A two - crust pie has the filling completely enclosed in the pastry shell . Shortcrust pastry is a typical kind of pastry used for pie crusts, but many things can be used, including baking powder biscuits, mashed potatoes, and crumbs . </P> <P> Pies can be a variety of sizes, ranging from bite - size to ones designed for multiple servings . </P>

Does a pie have to have a base