Place first 12 ingredients in a 6-qt. slow cooker. Cook, covered, on low until chicken is tender, 4-5 hours., Stir in cheese soup; heat through. If desired, top servings with avocado and additional cilantro. Freeze option: Freeze cooled soup in freezer containers. To use, partially thaw in refrigerator overnight. Heat through in a saucepan, stirring occasionally.