Cook the Pasta Shells

1. Boil Water: Bring a large pot of salted water to a boil.
2. Cook Jumbo Shells: Add the pasta shells and cook according to package instructions until al dente. Drain and set aside.

Prepare the Cheesesteak Filling

1. Sauté Vegetables: In a large skillet over medium heat, add the ground beef, diced onion, diced bell pepper, and minced garlic. Cook until the beef is browned and the vegetables are tender.
2. Season the Mixture: Stir in Worcestershire sauce, salt, and pepper. Remove from heat.
3. Combine Cheeses: In a mixing bowl, combine the beef mixture with provolone cheese and softened cream cheese. Mix until well combined.

Assemble the Stuffed Shells

1. Preheat Oven: Preheat your oven to 375°F (190°C).
2. Spread Marinara Sauce: Pour 1 cup of marinara sauce into the bottom of a 9×13-inch baking dish, spreading it evenly.
3. Stuff the Shells: Using a spoon, carefully fill each cooked jumbo shell with the cheesesteak filling, placing them in the baking dish.
4. Top with Sauce and Cheese: Pour the remaining marinara sauce over the stuffed shells and sprinkle with shredded mozzarella cheese.

Bake and Serve

1. Bake: Cover the baking dish with aluminum foil and bake for 25 minutes. Remove the foil and bake for an additional 15 minutes until the cheese is bubbly and golden.
2. Serve: Let the shells cool for a few minutes before serving. Garnish with fresh parsley if desired.