Preheat oven to 350°F.
Spray a 9x13 inch baking dish with nonstick spray. Spread the uncooked rice evenly into the prepared pan, then sprinkle with 1 cup of shredded cheese.
In a large glass measuring cup, combine the chicken broth and milk. Pour half of the mixture over the rice and cheese; stir to combine.
Cut the chicken breasts in half lengthwise, season with salt & pepper, and nestle them into the rice mixture in the pan.
Spoon the condensed cream of chicken soup evenly over the top.
Pour the remaining chicken broth and milk over the chicken breasts, then sprinkle the onion soup mix evenly over the top.
Bake, covered, at 350° for 1 hour 30 minutes or until rice is completely cooked.
Remove the pan from the oven, stir gently to combine the rice and sauce, and sprinkle the remaining 1 cup of cheese over the top. Return the pan to the oven for 5-10 minutes or until cheese is melted.
Let stand for 10 minutes; garnish with fresh parsley before serving. Sprinkle with salt & pepper to taste.