01 - Melt butter in a large soup pot over medium heat. Add diced onion, sliced carrots, and celery; sauté for 5 to 6 minutes until softened. Add minced garlic and cook for 1 minute.
02 - Add chicken pieces, bay leaves, dried thyme, salt, and pepper to the pot. Pour in chicken broth. Bring to a boil, then reduce heat, cover, and simmer for 25 to 30 minutes until the chicken is fully cooked.
03 - Remove chicken from the pot, shred the meat using two forks, discarding any bones. Return the shredded chicken to the pot.
04 - Stir frozen peas and chopped parsley into the soup. Bring the mixture to a gentle simmer.
05 - In a bowl, whisk together flour, baking powder, and salt. Stir in melted butter, whole milk, and optional parsley just until combined; avoid overmixing.
06 - Using a tablespoon, drop mounds of dumpling dough onto the simmering soup surface, spacing them evenly.
07 - Cover the 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 necessary. Ladle soup into bowls, garnish with additional parsley, and serve while hot.