Philly Cheesesteak Stuffed Shells

1. Preheat oven to 350°F (175°C).
2. In a large skillet, cook the ground beef over medium heat until completely browned. Remove the beef from the skillet and set aside. Drain any excess fat from the skillet.
3. Add butter to the skillet and melt over medium heat. Add diced onion and bell pepper, and sauté until softened, about 5 minutes.
4. Return the cooked beef to the skillet. Stir in Worcestershire sauce, ketchup, salt, and pepper. Cook the mixture for about 2 minutes, stirring occasionally.
5. Fill the cooked pasta shells with the beef mixture and arrange them in a single layer in a glass baking dish.
6. Place half of the cheddar cheese cubes into the stuffed shells.
7. In a medium saucepan, whisk together milk, beef broth, and cornstarch. Heat the mixture over medium heat until hot, then add the remaining cheddar cheese. Stir until melted and the sauce thickens. Pour half of the sauce over the stuffed shells in the baking dish.
8. Bake the stuffed shells at 350°F (175°C) for 10 minutes, or until the cheese is melted and bubbly.
9. Serve hot, with the extra cheese sauce on the side for dipping.

Prep Time: 15 minutes
Cooking Time: 25 minutes
Total Time: 40 minutes
Servings: 6