Sauté the Aromatics: Heat the butter or oil in a large pot over medium heat. Add the leeks, onion, and garlic. Sauté for 5-7 minutes until softened and fragrant.
Add Chicken and Stock: Add the chicken pieces (raw or cooked), then pour in the chicken stock. Stir in the carrots, celery, bay leaf, thyme, salt, and pepper. Bring the mixture to a simmer. Simmer: Let the soup simmer for about 20 minutes, or until the chicken is cooked through and the vegetables are tender. If you’re using leftover chicken, just heat it through.
Add Prunes (Optional): Add the prunes and continue to simmer for 5 minutes. This will give the soup a sweet, unique flavor.
Shred Chicken: Remove the chicken from the pot and shred it using two forks. Return the shredded chicken to the soup and stir well. Adjust Seasoning: Taste the soup and adjust the seasoning with more salt, pepper, or thyme if necessary.
Serve: Ladle the soup into bowls and garnish with chopped parsley. Serve hot with crusty bread or oatcakes.