Begin by bringing a large pot of salted water to a boil. Add your choice of pasta and cook according to package instructions for 1 minute less than al dente. Drain and set aside.

In a large skillet over medium-high heat, add the ground beef and cook until browned, about 5-7 minutes. Drain excess fat if necessary.

Add the diced onion, green bell pepper, and minced garlic to the skillet. Cook for 3-4 minutes until softened and fragrant.

Stir in the tomato sauce, ketchup, brown sugar, Worcestershire sauce, yellow mustard, salt, and black pepper into the skillet. Let simmer for 5-8 minutes until the sauce thickens.

Preheat your oven to 350°F (175°C), grease a 9x13-inch baking dish.

In the bowl with cooked pasta, combine the meat sauce and half of the shredded cheddar cheese. Stir until evenly coated.

Pour the pasta mixture into the greased baking dish, spreading it evenly. Sprinkle the remaining cheddar cheese on top and add crunchy toppings if desired.

Bake in the preheated oven for 20-25 minutes until bubbling and cheese is melted and golden.

Let the casserole rest for a few minutes before serving.