1 box macaroni and cheese
1 can cream of mushroom soup
1 small can of tuna, drained and flaked
1/2 c. milk
1/2 c. chopped onion (optional)
3/4 c. frozen peas (optional)
salt and pepper to taste
Preheat onion to 350 degrees, prepare macaroni and cheese according to directions on the box. Place remaining ingredients in a 2-quart casserole dish, and mix well. Stir in macaroni and cheese. Top with crushed chips or crackers if desired. Bake uncovered for 35 minutes.