1 pkg. shell macaroni
1 (8 oz.) sour cream
1 1/2 lbs. ground beef
1 pkg. taco seasoning
1 (15 oz.) tomato sauce
1 (8 oz.) Cheddar cheese
1 (8 oz.) Mozzarella cheese

Brown hamburger and add taco seasoning. Layer remaining ingredients in casserole dish - cooked shell macaroni, sour cream, tomato sauce, ground beef. Bake at 350 degrees for 30 minutes or microwave for 10 minutes.