HEAT oven to 375°F.
WHISK first 4 ingredients in 13x9-inch baking dish until blended.
ADD chicken, rice, broccoli and 1 cup cheese; mix well. Cover.
BAKE 30 min.; stir. Top with remaining cheese; bake 5 to 10 min. or until chicken is done. Let stand 5 min. or until liquid is absorbed.