Begin by placing the chicken and diced onion into the slow cooker, then add the chicken broth, salsa, taco seasoning, and cumin. Cover and cook on LOW for approximately 4 hours or until the chicken reaches an internal temperature of 165°F.
Once the chicken is cooked, remove it from the slow cooker and shred it using two forks. Return the shredded chicken back into the slow cooker.
Switch the slow cooker setting to HIGH and add the instant rice and black beans. Stir the mixture, cover, and cook for about 40 minutes until the rice is tender and the liquid has reduced.
Finally, top the mixture with the shredded cheese, cover, and let it cook for a few additional minutes until the cheese is melted.
Serve the dish in a bowl with your choice of toppings such as sliced olives, sliced green onion, and sour cream.