Preheat oven to 350°F. Lightly grease a 9 x 13 or 3-quart casserole dish. Prepare yellow rice according to package directions.
While rice is cooking, heat olive oil in large saucepan over medium high heat, add onion, red bell pepper and carrots and sauté for 10 minutes or until tender.
4. In a large bowl, combine hot cooked rice, sautéed onion, red bell pepper and carrots, black beans, diced tomatoes with chilies, chicken and 1 cup of cheese.
Transfer mixture into prepared casserole dish, sprinkle evenly with remaining 1 cup of cheese.
Cover with foil and bake for 30 minutes. Remove foil and bake for additional 10 minutes or until cheese is melted.
Serve and top with sour cream if desired.