Christmas Macaroni - cooking recipe

Ingredients

8 oz. macaroni, cooked and drained
1 small jar chopped pimentos
1/2 c. mayonnaise
1/2 small onion (optional)
1 can cream of mushroom soup
1/2 to 1 lb. grated Cheddar cheese or choice of cheese

Preparation

My children call it this because of red pimentos.