In a bowl, combine the first four ingredients. Stir in turkey, vegetables, salt and pepper. Spoon into a greased 11x7x2 inch baking dish. For crust, combine potato flakes, flour and Parmesan in a bowl; cut in butter until crumbly. Add water, 1 Tablespoon at a time, tossing lightly with a fork until the dough forms a ball. On a lightly floured surface, roll the dough to fit baking dish. Cut vents in crust, using a small tree or star cutter if desired. Place over filling; flute edges. Brush pastry with cream. Bake at 200ºC or 25-30 minutes or until golden brown. If necessary, cover edges of crust with foil to prevent overbrowning.