In a large skillet, add the diced onion and red bell pepper over medium heat. Sauté for about 3-4 minutes until the vegetables are softened and fragrant.
Add the ground beef to the skillet. Using a wooden spoon, break it apart as it cooks. Cook until the beef is browned and no longer pink, about 5-7 minutes. Drain any excess fat if necessary.
Stir in the tomato sauce, tomato paste, garlic salt, and beef broth. Mix well to combine all the flavors.
Add the uncooked macaroni noodles and the Tastefully Simple Mama Mia Marinara Sauce Mix to the skillet. Stir everything together, ensuring the noodles are fully submerged in the liquid.
Bring the mixture to a gentle boil, then reduce the heat to low. Cover the skillet and let it simmer for about 12-15 minutes, or until the pasta is cooked al dente and has absorbed most of the liquid.
Once the pasta is cooked, remove the skillet from the heat and sprinkle the shredded mozzarella cheese evenly on top. Cover the skillet again and let it sit for a few minutes until the cheese is melted and bubbly.
Gently stir the cheese into the pasta before serving. Dish out generous portions and enjoy with a side salad or crusty bread.