A frittata is a lot like soup. You can put just about anything in it that you want to. But it is not a catch-all for the old and discarded. It is a tool to re-purpose recent leftovers and extremely useful as a vehicle for stretching small amounts of delicious ingredients. Tonight we indulged in a frittata full of parmigiano-coated asparagus, pepperoni stewed potatoes, and fresh mozzarella cheese. It was hearty, rich and utterly satisfying. An extra bonus is that the leftovers will be even better tomorrow morning for breakfast.