Boil 1 pound box elbow macaroni until soft. Mix macaroni and 1/2 pound can whole tomatoes, chopped, in mixing bowl. Slice 1 pound block of cheddar cheese into 1/4 inch slices. Layer macaroni and cheese in casserole bowl. Add 1 cup water. Bake at 350 degrees for 45-60 minutes until cheese is fully melted