Creating the incredible Philly Cheesesteak Casserole is easy when you follow these step-by-step instructions:

1. Preheat Oven: Preheat your oven to 350°F (175°C) and prepare a baking dish (9×13 inches) by lightly greasing it.
2. Cook the Steak: In a large skillet, heat olive oil over medium-high heat. Add the sliced steak, garlic powder, onion powder, salt, and black pepper. Sauté until the steak is browned, about 5-7 minutes.
3. Add Vegetables: Add the sliced onions and bell peppers to the skillet. Stir in the soy sauce and continue to cook until the vegetables are soft, about 3-4 minutes.
4. Combine with Pasta: In a large mixing bowl, combine the cooked pasta with the steak and vegetable mixture. Pour in the beef broth and mix thoroughly.
5. Layer Cheese: Transfer half of the pasta mixture into the greased baking dish. Sprinkle 1 cup of cheese over the top. Then, add the remaining pasta mixture and top with the remaining cheese.
6. Bake: Place the baking dish in the preheated oven and bake for 30-35 minutes or until the cheese is melted and bubbly.
7. Garnish: Remove the casserole from the oven and let it cool for a few minutes. Garnish with fresh parsley if desired.
8. Serve: Cut into squares and serve warm.

These simple steps will help you create a delicious Philly Cheesesteak Casserole that will impress your family and friends.