Preheat the oven to 350 degrees Fahrenheit.
Grease a 9 x 13 inch baking dish with non-stick spray and set aside.
In a medium sized bowl combine the white rice, cream of mushroom and chicken soup and chicken broth. Mix until combined. Pour into the prepared baking dish.
Place chicken breasts on top of the rice mixture. Sprinkle the onion soup mix on top of the casserole evenly. Cover the baking dish with aluminum foil and place in a preheated oven.
Bake for 1 hour and 15 minutes or until the chicken reaches an internal temperature of 165 degrees Fahrenheit.
