Prepare the macaroni and cheese according to the package directions.
Meanwhile, in a large skillet or Dutch oven, cook the ground beef, onion, bell pepper, and garlic over medium-high heat until the meat is no longer pink. Drain off the excess grease.
Stir in the tomato sauce, corn, and diced tomatoes. Gently simmer over low heat for about 5 minutes, stirring regularly.
Add the cooked macaroni and cheese to the beef mixture; stir to combine. Taste and season with salt and pepper if desired.
Garnish with chopped fresh herbs or sliced green onions; serve immediately.
