Leftover beef stew easily became this very palatable beef and vegetable pie. Place remaining leftover stew into a baking dish. Make your favourite pastry recipe or use a ready made puff pastry, roll the pastry out to the size of dish. Place the pastry on top. Cut slits in the pastry to allow venting, then brush melted butter over top. Pop in the oven until the stew is bubbling and the pastry is baked to a lovely golden brown.