Cook 16 ounces elbow macaroni according to package directions.
Chop ½ onion and mince 2 teaspoons garlic.
Brown 1 pound ground beef in a skillet with chopped onion and minced garlic.
Add 2 tablespoon taco seasoning mix and ⅓ cup water and simmer for 2 minutes. Stir in 1 cup tomato sauce, 1 cup water, ¼ cup milk, 10 ounces Rotel tomatoes and green chilies (drained), ¼ teaspoon salt, ¼ teaspoon pepper, and cooked pasta. Cook over medium heat until heated through.
Stir in 1 cup shredded cheddar cheese and serve immediately.
Notes
If you already have taco-seasoned ground beef in the freezer, this recipe can be done in about 15 minutes. If you don't have any stockpiled, go ahead and cook extra tonight and freeze it. Cooking 5 lbs. ground beef and seasoning it for the freezer takes less time than making 1 lb. ground beef 5 times and seasoning it for each recipe.