Give macaroni and cheese southwest flavors and turn it into a main dish recipe. This casserole layers a chili-style ground beef mixture between layers of macaroni and cheese spiked with cumin and chipotle chili powder.
Heat oven to 375 degrees F. Coat a rectangular 13 x 9 x 2-inch baking dish with nonstick cooking spray.
Heat a large nonstick skillet over medium-high heat. Crumble in beef and add the onion. Cook for 6 to 7 minutes or until beef is no longer pink. Stir in tomato paste, 1-1/2 teaspoons of the chile powder, 1 teaspoon of the cumin and 1/4 teaspoon of the salt. Add 1/4 cup water and cook 1 minute. Set aside.
Meanwhile, cook pasta following package directions. Drain and set aside.
While pasta is cooking, make the sauce. In a medium-size saucepan, stir together milk, flour, the remaining 1-1/2 teaspoons chile powder, 1 teaspoon cumin and 1 teaspoon salt. Bring to a simmer and cook for 1 minute until thickened. Off heat, stir in 1 cup of the cheddar and 1 cup of the pepper-Jack cheese until a smooth sauce is formed.
Stir the cheese sauce into the pasta. Spoon half of the mixture into the prepared baking dish. Top with the beef mixture and then the remaining pasta. Sprinkle the remaining cheese and crushed chips over the top. Bake at 375 degrees F for 30 minutes until bubbly and browned.