Heat a large pot over medium-high heat. Add the olive oil, onions, carrots, and celery. Sauté until the veggies are softened — about five minutes.
Rinse the barley. Add it to the pot along with the chicken thighs, broth, bay leaves, salt, and pepper.
Bring the soup to a boil, then reduce the heat to low. Simmer until the chicken is cooked — about 20 minutes. Remove the chicken and cut or shred the meat. Stir it back into the pot. Cook the soup on low heat for another 20 minutes, or until the barley is tender.
Taste for seasoning and garnish the soup with fresh, chopped parsley. Serve it warm and enjoy!