Place ingredients in a 9-1/2 X 13 inch baking dish in layers. Chicken on the bottom covered by the steamed broccoli and topped with the fresh mushrooms. The broccoli only needs to be steamed enough to remove the excess water. Cover with aluminum foil and place in preheated 325ø-350°F oven for 30 minutes. Remove from oven and place 1/4" thick slices of Velveta Cheese on top and return to oven until cheese melts.
