1Preheat oven to 400. Prepare mac and cheese as directed on package. While mac and cheese is cooking, brown hamburger meat and drain. Add taco seasoning and water to meat and simmer 5 mins.
2Stir sour cream into mac and cheese. Spoon half of the mac and cheese mixture into a 9X9 baking dish; top with all the hamburger meat; top meat with 1 cup of the cheese and then the remaining mac and cheese. Cover and bake for 15mins.
3Then top with salsa and remaining cheddar cheese and bake uncovered for another 5mins or until cheese is melted.