Taco Bake

1 pkg. (14 oz.) KRAFT Deluxe Macaroni & Cheese Dinner
1 lb. ground beef
1 pkg. (1-1/4 oz.) TACO BELL® HOME ORIGINALS® Taco Seasoning Mix
3/4 cup BREAKSTONE'S or KNUDSEN Sour Cream
1-1/2 cups KRAFT Shredded Cheddar Cheese, divided
1 cup TACO BELL® HOME ORIGINALS® Thick 'N Chunky Salsa


HEAT oven to 400°F. Prepare Dinner as directed on package. While Macaroni is cooking, cook meat with taco seasoning as directed on package.
STIR sour cream into prepared Dinner; spoon 1/2 into 8-inch square baking dish. Top with layers of meat mixture, 1 cup cheese and remaining Dinner mixture; cover with foil.
BAKE 15 min.; top with salsa and remaining cheese. Bake, uncovered, 5 min. or until cheese is melted.