Family Taco Casserole
["6 c. tortilla chips (about 6 oz.)", "1 lb. ground beef", "1/4 c. chopped onion", "1 (8 oz.) can tomato sauce", "1/2 c. water", "1 (1 1/4 oz.) envelope taco seasoning mix", "1 c. light sour cream", "1 c. Mozzarella cheese", "shredded lettuce", "chopped tomatoes"]
["Crush tortilla chips to coarse crumbs.", "Set aside.", "Crumble ground beef into medium-size glass bowl.", "Add onion.", "Microwave on High for 5 minutes, stirring 3 times.", "Drain fat.", "Stir in tomato sauce, water and seasoning mix.", "Microwave on High until boiling (about 3 minutes)."]
["tortilla chips", "ground beef", "onion", "tomato sauce", "water", "taco", "light sour cream", "Mozzarella cheese", "shredded lettuce", "tomatoes"]