01 - Place chicken thighs, diced onion, sliced carrots, celery stalks, minced garlic, chicken broth, dried thyme, dried parsley, bay leaf, salt, and black pepper in the slow cooker. Stir thoroughly to distribute ingredients evenly.
02 - Cover the slow cooker and cook on low heat setting for 5 hours until chicken becomes tender and fully cooked through.
03 - Carefully remove chicken thighs from the slow cooker. Using two forks, shred the meat into bite-sized pieces. Return shredded chicken back to the slow cooker.
04 - In a medium saucepan over medium heat, melt 2 tablespoons butter. Whisk in 3 tablespoons flour and cook for 1 minute while stirring constantly. Gradually whisk in 1 cup milk and 0.25 cup heavy cream until mixture becomes smooth and slightly thickened. Pour the creamy mixture into the slow cooker and stir well to incorporate.
05 - In a mixing bowl, combine 1.5 cups flour, baking powder, and 0.5 teaspoon salt. Cut in 2 tablespoons cold butter until mixture resembles coarse crumbs. Stir in 0.75 cup milk and chopped fresh parsley until just combined. Avoid overmixing to maintain fluffy texture.
06 - Drop rounded spoonfuls of dumpling batter, approximately 2 tablespoons each, onto the surface of the stew. Cover and cook on high heat for 1 hour until dumplings are cooked through and fluffy.
07 - Remove and discard the bay leaf. Ladle hot chicken and dumplings into serving bowls. Serve immediately while hot.