Preheat the oven to 375 degrees. Grease a 9"x13" baking dish with cooking spray.
Add the rice to the baking dish, spreading it out evenly. Pour in the chicken broth.
In a large bowl, add the chicken, fajita seasoning, bell peppers, onions, and salsa. Stir to combine.
Layer the mixture on top of the rice.
Cover casserole with foil and bake for 55 minutes. Sprinkle cheese on top and cook another 5 minutes, or until cheese is melted.
Serve casserole with sour cream, chopped scallions, cilantro, lime wedges, or hot sauce, if desired.