If not using pre-cooked chicken, bake chicken until cooked or dice and sauté in a skillet.
Place the butter in the bottom of a 9x13 baking dish.
Add the broccoli, cauliflower, and diced onion.
Cook in the oven for 20-25 minutes or until heated and mostly cooked.
While the vegetables are heating, chop the chicken into bite sized pieces and grate the cheese if necessary.
Remove the vegetables from oven.
Add the chopped chicken, cheddar cheese, sour cream, spices, and ¼ cup water to the vegetables and mix well.
Top with Parmesan if desired and return the baking dish to the oven.
Continue cooking until the cheese is melted and everything is heated through.
Notes
The time frame listed for this recipe applies to use of pre-cooked chicken and diced frozen vegetables. Make and extra batch and freeze it for an easy meal another time!