1 can cream of mushroom soup
1 sm. can pimientos, chopped
1 lb. grated cheddar cheese
1 med. onion, chopped
1 tbsp. mayonnaise
1 c. uncooked macaroni
Ritz cracker crumbs

Mix all ingredients except cracker crumbs. Pour into a greased casserole dish. Sprinkle crumbs on top. Bake at 325 degrees for 45 minutes.