Add broth, beans, carrots, celery, onion, garlic, salt, pepper and bay leaf to a slow cooker. Stir to combine. Add the ham bone and submerge in broth. Cover and cook on HIGH until beans are tender, 6-8 hours.
Discard bay leaf. Remove ham bone and let sit until cool enough to handle. Once cool, dice any ham meat and stir it back into the soup.
Season soup with additional salt and pepper, to taste. Ladle into bowls and garnish with fresh parsley.
