Au Gratin Chicken Bake

Made Au Gratin Chicken Bake for Stephen and Willow today. Unfortunately I don't eat cheese so they had to be my taste testers. Willow didn't eat much of hers - I think mostly because it contained potatoes, of which she will only really eat in mashed form, but Stephen said it was a definite keeper and gobbled his up. This one is a really quick meal to make that smells and looks great.

Au Gratin Chicken Bake
(My changes in italics)

1 bag (14 oz) Green Giant Select® frozen broccoli florets, thawed and drained (I estimated amount and only defrosted for five minutes or so)
1 box (7.8 oz) Betty Crocker® Deluxe creamy Cheddar au gratin potatoes
2 cups boiling water
2 tablespoons margarine or butter
1/2 cup milk
2 boneless skinless chicken breast halves (pounded thin and seasoned with lawry's all-purpose seasoning, garlic powder, salt and pepper, and paprika)
2 slices (1 oz each) Cheddar cheese, cut diagonally in half (I subbed shredded cheddar and a little mozzarella)

1.Heat oven to 400ºF. Spray 11x7-inch baking dish or 2-quart casserole with cooking spray.
2.Spread broccoli in baking dish. Stir Potatoes, Sauce Mix, Cheese Sauce, boiling water and margarine in medium bowl. Stir in milk. Spread over broccoli. Place chicken breast halves on potato mixture.
3.Bake uncovered 30 minutes. Place cheese slices on chicken. Sprinkle with Topping. Bake 3 to 5 minutes longer or until cheese is melted and juice of chicken is no longer pink when centers of thickest pieces are cut. Let stand 5 minutes or until sauce is as thick as desired.