Cook the macaroni according to instructions on the package.
In the meantime, place beef and onion in a large saucepan over medium heat, breaking up the meat and until the beef is no longer pink.
Add garlic and cook 1 minute longer. Drain.
Stir in diced tomatoes, kidney beans, tomato paste, chiles, salt, chili powder, cumin, black pepper. Bring to a boil, then reduce heat and allow to simmer, uncovered for 10 minutes.
Drain macaroni, and add to beef mixture. Stir to incorporate.
Preheat oven to 375° F. Transfer contents of the saucepan to two 2-quart casserole baking dishes.
Top with cheese and jalapenos, dividing accordingly to cover both casseroles.
Cover and bake for 30 minutes. Uncover, continue to bake until bubbly and heated through for about 10 minutes longer or until bubbly and heated through.
Serve 1 casserole. Cool the second; cover and freeze for up to 3 months.