Season the ground beef with half of the salt and pepper. Shape the beef into small meatballs, approximately 1 tablespoon in size.
Cut the cabbage in half and slice it into thin strips.
Place the chicken breasts, meatballs, diced tomatoes, cabbage, seasonings, and chicken stock into your slow cooker.
Cover and cook on low for 7–8 hours or on high for 4–5 hours, until the chicken is fully cooked and tender.
Once done, shred the chicken directly in the slow cooker using two forks, or remove it, shred it, and return it to the soup.
Ladle the soup into bowls and garnish with your favorite toppings, such as avocado slices, a squeeze of lime juice, chopped cilantro, sour cream, and shredded cheese.