1 1/4 lb. ground beef
Oil for browning
1 lg. onion, chopped
1 (14 oz.) jar spaghetti sauce
1 (4 oz.) can mushrooms, undrained
1 pt. sour cream
1 (8 oz.) pkg. sliced Provolone cheese
1 (8 oz.) pkg. sliced Mozzarella cheese
9 or 10 oz. med. shell macaroni

Cook ground beef in vegetable oil until brown; drain off excess fat. Add onion, mushrooms and spaghetti sauce; simmer 20 minutes; until onions are soft. Stir in sour cream; heat.

Cook, drain and rinse macaroni. Place half in a deep 3-quart casserole; cover with half the meat sauce, top with slices of Provolone. Repeat, ending with slices of Mozzarella.

Cover and bake at 350 degrees for 35 to 40 minutes. Remove cover and continue baking until cheese melts and brown slightly. Can use 2 (1 1/2 quart) casseroles. Can be kept refrigerated for a few days before baking.