In a large skillet over medium heat, add olive oil and sauté the broccoli florets for about 3-5 minutes until tender. If using frozen broccoli, cook until heated through.
In a large mixing bowl, combine the cooked rotini, shredded chicken, sautéed broccoli, Alfredo sauce, garlic powder, Italian seasoning, salt, and pepper. Mix well until all the ingredients are coated with the sauce.
Transfer the mixture into a greased 9x13 inch baking dish.
Sprinkle mozzarella cheese and Parmesan cheese evenly on top. If desired, add breadcrumbs for a crunchy topping.
Cover the baking dish with aluminum foil and bake in the preheated oven for 20 minutes.
Remove the foil and bake for an additional 10-15 minutes, or until the cheese is bubbly and slightly golden.
Remove from the oven and let cool for 5 minutes before serving.
Notes
Feel free to use store-bought Alfredo sauce for convenience.