1/2 c. chopped onion
2 tbsp. butter
1 can cream of mushroom soup
1/2 c. canned tomatoes, drained
1 c. peas, cooked
2 c. med. noodles, cooked
2 c. drained tuna
Cheese slices and croutons

Saute onion in butter until tender. Stir in ingredients except cheese and croutons. Pour into greased 2 quart casserole. Bake at 400 degrees for 20 minutes. Remove from oven and stir top with cheese slices and croutons. Return to oven until cheese melts.