Preheat oven to 400 degrees F. Combine beef and seasoning mix in large skillet. Cook over medium-high heat, stirring occasionally, for 2 to 3 minutes or until beef is no longer pink.

 

Combine one package macaroni and cheese and sour cream in medium bowl; spread over bottom of 8 inch square baking dish. Top with beef mixture. Spread remaining package macaroni and cheese over beef mixture; top with tomato, potato chips and cheese. Bake for 20 to 25 minutes or until bubbly around edges.