Peter Pots Pottery has long been famous for its casseroles, and our pie plates are a customer favorite. Discover why stoneware makes excellent bakeware for yourself! All our casseroles, beanpots, and pie plates are ovenproof. They are not intended for use under the broiler and should never be used on the stovetop. We recommend that our bakeware be at least 3/4 full for even heating.