1. Add the onion, garlic, diced tomatoes, tomato sauce, chicken broth, black beans, corn, green chiles, chili powder, cumin, smoked paprika, oregano, salt, and black pepper to the slow cooker and stir well.

2. Nestle the chicken breasts into the liquid so they are mostly covered.

3. Cover and cook on low for 6 to 7 hours or on high for 3 to 4 hours, until the chicken is tender and fully cooked.

4. Remove the chicken, shred it with two forks, and return it to the slow cooker.

5. Stir in the lime juice and chopped cilantro, then let the soup sit for 5 minutes.

6. Ladle into bowls and top with tortilla strips, avocado, cheddar cheese, and sour cream before serving.