Preheat oven to 375 degrees.
Set a stock pot to boil for the pasta. While the penne pasta is cooking, cut up your boneless, skinless chicken breasts and season them with salt and pepper.
Add the chicken to a pan coated with olive oil. Cook over medium heat until the chicken is no longer pink.
Drain the pasta when done and return to the stock pot. Add in the broccoli florets, chicken, Alfredo sauce, garlic powder and salt and pepper to taste. Mix well.
Spray a 9x13 baking dish with cooking spray. Pour mixture from stock pot into the casserole dish and top with the Parmesan cheese.
Add the shredded mozzarella to the top of the dish.
Bake at 375 degrees for 25-30 minutes.