Add the broccoli to a large microwave safe bowl along with 2 tablespoons of water. Cover tightly with plastic wrap and microwave for 2 minutes. Let sit, covered, for 2 minutes.
Carefully remove the plastic wrap and drain the liquid.
Add the cream cheese, mayonnaise, cheddar, garlic powder, salt, and pepper to a small bowl and mix well to combine.
Stir the cream cheese mixture and chicken into the steamed broccoli until well combined.
Transfer broccoli to a 9x13 baking dish and sprinkle the Parmesan over the top.
Bake for 15 minutes.
Video
Notes
Use pre-cut broccoli florets to keep it extra easy.Rotisserie chicken, leftover cooked chicken, or the frozen chunks of grilled chicken you can buy at the store all work well in this recipe. If you using frozen chicken, thaw before adding to the casserole.