3 c. cooked macaroni
2 c. grated cheese
1/2 c. mayonnaise
1 med. onion, sauteed
1 sm. bottle chopped pimentos
1 can mushroom soup
Ritz cracker crumbs

Chop and saute onion. Mix together and pour into casserole. Top with cracker crumbs. Dot with butter. Bake at 350 degrees until light brown and bubbly.