Combine the chicken, diced tomatoes and their juices, chicken broth, chili powder, salt, and cumin in a slow cooker. Make sure the chicken is covered with liquid, adding additional broth as needed. Cover and cook on the LOW setting for 3 to 4 hours.

Uncover and stir in the beans, rice, and corn. Cover and continue cooking on the LOW setting for 3 to 4 hours more. Check the rice periodically in the last hour of cooking, stirring once or twice to make sure the rice cooks evenly and adding more chicken broth if the mixture seems dry. Cooking is done when the rice is tender — if the rice is done but there is still liquid left in the slow cooker, uncover and cook on the HIGH setting to let the liquid evaporate.

Use 2 forks to shred the chicken into bite-sized pieces. You can do this either in the slow cooker itself and then mix it into the rice, or you can transfer the chicken to a clean cutting board if you prefer to keep it separate. Taste and stir in more salt or other seasonings as needed. Serve burrito bowls with a selection of toppings.