This is a recipe from allrecipes that my 10 year old daughter made for dinner one night. Simple and tasty. I think next time, I'll add some veggies to it too - and maybe switch out the tuna for some canned chicken.
3 cups cooked macaroni
1 (6 oz) can tuna, drained
1 can cream of chicken soup
1 cup Cheddar cheese, shredded
1 1/2 cups French Fried Onions
Preheat oven to 350 degrees.
Combine macaroni, tuna, and soup in square baking dish. Top with cheese.
Bake for 25 minutes or until bubbly. Sprinkle with French Fried Onions and bake another 5 minutes.