Sheets of pasta which are layered with sauce and cheese and baked au gratin. Meat, fish, shellfish, and vegetables are all used as fillings for this dish. Recipes from northern Italy are simple preparations consisting of little more than sauce and cheese. Contrary to this is lasagna al forno, filled with a rich bolognese sauce. Southern Italian versions are more elaborate calling for the addition of sausages, mushrooms, and anything else they may have on hand.
