Preheat the oven to 350°F (175°C).
Mix the rice base. In a large bowl, combine the uncooked rice, chicken broth, cream of mushroom soup, mushrooms, garlic, and onion soup mix.
Season the chicken. Mix the garlic powder, onion powder, and paprika together. Add salt and pepper to taste. Sprinkle the mixture over the chicken to season it.
Assemble the casserole. Pour the rice mixture into a greased 9x13 baking dish. Nestle the chicken pieces into the rice, spacing them evenly. Sprinkle a little extra paprika over the top for color.
Bake covered for about 1 hour, or until the rice is tender and the chicken reaches 165°F internal temperature.
Optional: Remove the cover during the last 10 minutes to let the top brown slightly.