01 - Place chicken, carrots, celery, onion, garlic, chicken broth, thyme, parsley, salt, and black pepper into the slow cooker and stir to combine.
02 - Cover and cook on low heat for 5 hours, until chicken and vegetables are tender.
03 - Melt 2 tablespoons of butter in a saucepan over medium heat. Stir in 3 tablespoons of flour and cook for 1 minute, then gradually whisk in heavy cream until smooth and thickened. Remove from heat.
04 - Using two forks, shred the chicken directly in the slow cooker.
05 - Stir the prepared cream sauce into the slow cooker mixture.
06 - In a bowl, combine 1 cup flour, baking powder, and salt. Cut in cold cubed butter until mixture resembles coarse crumbs. Stir in milk until just combined without overmixing.
07 - Drop tablespoon-sized portions of dumpling dough evenly over the stew in the slow cooker.
08 - Cover and cook on high for 45 to 60 minutes, until dumplings are fully cooked and fluffy.
09 - Taste and adjust seasoning if necessary before serving.