Place the chicken breasts in the bottom of a 6-quart slow cooker.
Add the onion, garlic, black beans, tomatoes, green chiles, chicken broth, cumin, chili powder, salt, and pepper to the slow cooker and stir to combine.
Cover and cook on low for 4-6 hours, or on high for 2-3 hours.
Once the chicken is cooked through, remove it from the slow cooker and shred it using two forks. Return the shredded chicken to the slow cooker.
Stir in the corn, sour cream, and cilantro, and cook for an additional 15 minutes.
Serve in bowls topped with cheddar cheese.
Interesting Facts
This soup is a great way to use up leftover chicken.
You can add other vegetables, such as bell peppers, mushrooms, or zucchini, to the soup.
If you don't have a slow cooker, you can make this soup on the stovetop.