Step 1: Preheat your oven to 350°F (175°C) to ensure even cooking.
Step 2: Cook your rotini pasta according to package instructions until al dente. Drain and set aside.
Step 3: In a large mixing bowl, combine the cooked pasta, shredded chicken, steamed broccoli, and Alfredo sauce. Add garlic powder, onion powder, salt, and pepper. Mix until coated.
Step 4: Gently fold in the mozzarella cheese, reserving some for topping.
Step 5: Pour the mixture into a greased 9x13 inch baking dish, spreading it evenly.
Step 6: In a small bowl, mix breadcrumbs with olive oil until evenly coated.
Step 7: Sprinkle the breadcrumb mixture over the pasta mixture, then top with reserved mozzarella and Parmesan cheese.
Step 8: Bake for 25-30 minutes, or until the top is golden brown and bubbly.
Step 9: Let it cool for a few minutes before serving to help it set.