Combine your spices and mix them with the rice and water. Boil the rice mixture for 20 minutes.
Preheat your oven to 425 degrees.
When the rice is fully cooked and fork-tender, place it in the bottom of a cast iron skillet in a layer across the bottom. Add chicken across the top of the rice in a layer.
Top chicken with the bell pepper.
Add the green onion on top of the bell pepper.
Cover the entire casserole with cheese then bake for 15 minutes.
Allow the Mexican chicken and rice casserole to cool and then serve!