In a large skillet, cook chicken over medium heat in oil for 3-4 minutes on each side or until a thermometer reads 165°. Remove from pan; keep warm. Add the celery, onions and peppers; cook until vegetables are crisp-tender. Stir in beans and mushrooms until heated through., Stir in the broth, water, garlic and seasonings. Bring to a boil. Stir in rice; cover and remove from the heat. Let stand for 5 minutes or until rice is tender; fluff with a fork. To serve, top rice mixture with chicken breasts.