Put flour and salt in bowl. Using fingers or a pastry blender, cut butter and shortening into flour. Working quickly, lightly rub flour and fat through finger tips until mixture is fine and mealy. Start mixing the dough gently as you add cold milk, 1 tablespoon at a time. Add milk until mixture just fathers into a firm yet crumbly ball. Do not exert any pressure to force the dough together. The less milk you use the flakier the pastry will be.
Roll the dough between 2 sheets of wax paper. Line the pan with the dough. Prick all over the inner surfaces, including the sides, with the tines of a fork. Paint the surface with a very small amount of unbeaten egg white. Fill with the quiche recipe of your choice and bake as directed.
