Preheat the Oven: Preheat your oven to 350°F (175°C).
Cook the Ground Beef: In a large skillet, heat a little olive oil over medium heat. Add the ground beef and cook until browned, breaking it apart as it cooks (5-7 minutes). Drain any excess fat.
Add Vegetables: Add chopped onion and bell pepper to the skillet and cook until softened (3-4 minutes). Stir in the mixed vegetables and cook for an additional 5 minutes.
Season the Mixture: Add garlic powder, paprika, salt, and pepper to taste. Stir everything together and simmer for another 5 minutes.
Add Tomato Sauce: Pour in tomato sauce and diced tomatoes, stirring to combine. Let the mixture simmer for 10 minutes, allowing the flavors to meld.
Cook the Pasta: While the beef mixture simmers, cook the pasta according to package instructions. Drain the pasta and set aside.
Assemble the Casserole: In a greased 9x13-inch baking dish, combine the cooked pasta with the beef and vegetable mixture. Stir to combine evenly.
Top with Cheese: Sprinkle the shredded cheddar cheese over the top.
Bake: Place the casserole in the preheated oven and bake for 20-25 minutes, or until the cheese is melted and bubbly.
Serve: Let the casserole rest for 5-10 minutes before serving. Serve with cornbread or a fresh salad, if desired.
