Preheat the oven to 400 F.
To a 9x13-inch baking dish, add the brown rice (uncooked), rinsed black beans, frozen corn, frozen fajita veggies, salsa verde and cumin. Gently combine all the ingredients in the baking dish.
Pour the chicken stock over the top and gently combine to remove any air bubbles. Cover the baking dish tightly with foil.
Bake in the preheated oven for 45 minutes, then remove the foil and bake another 10 minutes. Let cool before serving. Season with salt and pepper to taste.
Serve Fajita Rice & Bean Bake as is, or with toppings like avocado slices, shredded cheese and sour cream.