01 - Melt butter in a large soup pot over medium heat. Add diced onion, sliced carrots, and celery; sauté until softened, about 5-6 minutes. Stir in minced garlic and cook for 1 minute.
02 - Add chicken, bay leaves, dried thyme, salt, and black pepper to the pot. Pour in the chicken broth. Bring to a boil, then reduce heat to low. Cover and simmer for 25-30 minutes or until chicken is fully cooked.
03 - Remove chicken from pot and shred meat using two forks, discarding bones. Return shredded chicken to the soup.
04 - Stir in frozen peas and chopped parsley. Bring the soup back to a gentle simmer.
05 - In a mixing bowl, whisk together all-purpose flour, baking powder, and salt. Fold in melted butter, whole milk, and optional parsley until just combined, avoiding overmixing.
06 - Spoon tablespoon-sized mounds of dumpling batter onto the surface of the simmering soup, spacing them evenly.
07 - Cover pot tightly and simmer without removing the lid for 15 minutes, until dumplings are puffed and cooked through.
08 - Remove bay leaves. Taste and adjust seasoning as needed. Ladle the soup into bowls, garnish with additional parsley, and serve warm.