In a large bowl, combine 2 cups cooked white rice, 1 cup shredded cooked chicken, 1 can rinsed black beans (optional), 1/2 cup finely diced onion, 1/2 cup finely diced red peppers, 1 chopped avocado, 1 t chili power, 1 t cumin, 1 t garlic powder, chopped cilantro to taste.
One by one, spread a thin layer of sour cream on a large tortilla, followed by shredded cheese. Place a large scoop of the filling inside and wrap tightly. Then in a large skillet, brown all sides of burrito in 2 T of cooking oil. Bake in the oven for 15 min at 350 until hot throughout.