Preheat oven to 350 degrees F (175 degrees C). Grease a 3 1/2 quart casserole dish.
In a saucepan, bring water to a boil. Stir in rice, reduce heat, and cover. Simmer for 20 minutes.
In a wok or large skillet, heat the broth and saute the garlic, bell pepper and onion until tender, about 5 minutes. Stir in cooked rice, cream-style corn, Mexican-style corn, whole kernel corn, diced tomatoes with chiles, green chiles, Mexican-style processed cheese, salt, pepper and chili powder. Spoon into prepared casserole dish.
Bake in preheated oven for 30 minutes, or until bubbly. Top with shredded Cheddar, cover and bake 5 minutes more. Remove from oven, uncover and let stand 10 minutes.
