Preheat oven to 350 degrees. Spray a 9 x 13 baking dish with non-stick cooking spray.
In a medium sauce pan, bring water & butter to a boil allowing butter to melt. Stir in stove top stuffing mix and continually mix until all bread cubes are coated well and water has been absorbed. Remove pan from heat and set aside.
Place shredded rotisserie chicken into bottom of prepared baking dish. Sprinkle diced onion across the chicken evenly.
Prepare broccoli & cheese in microwave per instructions on box. NOTE: cook for 4 minutes only. Spoon the broccoli & cheese sauce on top of the onion & chicken in baking dish evenly.
In a medium bowl whisk together 2 cans cream of chicken soup, sour cream, kinder seasoning, and milk. Pour mixture all over the ingredients in baking dish evenly.
Fluff up the stuffing and distribute it evenly all over the mixture in baking dish.
Bake in preheated oven for 35-40 minutes until golden brown on top and the mixture is heated through and bubbly.
