Start by spraying crock-pot with Pam or non-stick spray to prevent sticking.
Combine the chicken, diced tomatoes and their juices, chicken broth, chili powder, salt, and cumin in a 2.5 to 3.5 quart slow cooker. Make sure the chicken is covered with liquid, adding additional broth as needed.
Cover and cook on LOW for 3-4 hours.
Uncover at around the 4 hour mark 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 two forks to shred the chicken into bite-sized pieces by transferring the chicken to a clean cutting board or bowl and returning to the slow cooker once completed.
Taste and stir in more salt or other seasonings as needed. Serve burrito bowls with a selection of toppings (including but not limited to: shredded cheese, chopped cilantro, sliced avocado, salsa, hot sauce, sliced green onions, or shredded lettuce/spinach).