Heat 1 tablespoon olive oil and butter over medium-high heat in a large stockpot or Dutch oven. Season chicken with salt and pepper and cook on both sides until golden brown, about 2-3 minutes per side. Remove and set aside.
Heat remaining tablespoon olive oil and butter over medium heat and add onion, carrots and celery. Cook, stirring occasionally, for about 5-7 minutes or until tender. Add garlic and thyme and cook for another minute.
Add chicken broth and bay leaves and bring to boil. Stir in orzo, rosemary and chicken. Reduce heat and simmer until orzo is tender, about 12 minutes. Stir in lemon zest, lemon juice and parsley. Taste and season with salt and pepper if needed. Serve immediately.
Notes
Use pre-shredded rotisserie chicken to make the soup even quicker.
Use quality low-sodium chicken broth as it contributes to the flavor. You can also use chicken stock which gives the chicken barley soup more mouth feel.
You know the chicken is cooked when it reaches 165°F with an instant-read thermometer or if you cut into the chicken and the juices run clear and there is no pink. Honestly, I always just cut the chicken to see when it is done. If it isn’t just cook slightly longer.
The soup is great for leftovers but the orzo soaks up the broth so just add more broth.