Preheat the oven to 350 degrees. Grease a 9x13 baking dish with cooking spray, set aside.
In a large bowl mix together the cream cheese, sour cream, mayo, Parmesan, salt, pepper, onion and garlic powder. Fold in the chicken, broccoli and bacon until the ingredients are coated with the cheese mixture. Spread into the prepared baking dish and top with the shredded cheddar. Bake for 20-30 minutes or until the cheese is golden brown and the broccoli is tender. Serve with a salad.