01 - Place chicken, chicken broth, onion, carrots, celery, garlic, thyme, parsley, black pepper, salt, and butter into the slow cooker. Stir well to combine.
02 - Cover and cook on LOW for 6 hours or HIGH for 3 hours, until chicken and vegetables are tender.
03 - Remove chicken from the slow cooker, shred using two forks, then return shredded chicken to the slow cooker.
04 - Stir in the heavy cream thoroughly.
05 - In a bowl, whisk together flour, baking powder, and salt. Stir in melted butter, milk, and parsley until just combined, avoiding overmixing.
06 - Drop spoonfuls (approximately 1 tablespoon each) of dumpling batter onto the surface of the soup.
07 - Cover and cook on HIGH for 30 to 40 minutes until dumplings are fully cooked and fluffy.
08 - Serve hot, garnished with additional parsley if desired.