Add chicken, broth, beans, onion, and seasonings to slow cooker. Cover and cook on high 2-3 hours, or on low 4-5 hours.
about 30 minutes before serving, add cream cheese. Cover and cook another half hour.
Uncover, stir to mix cream cheese into soup and shred chicken with two forks. Taste, add salt and pepper to taste as needed. Stir in chopped cilantro. Serve hot and top with shredded cheese and avocado slices if desired.