Sauté the aromatics. Warm 2 tablespoons of olive oil in a large pot over medium heat.
Add onion, carrots, and celery with a pinch of salt. Cook 5–7 minutes, stirring, until soft and lightly golden.
Add the garlic and herbs. Stir in minced garlic, dried oregano or thyme, and a pinch of red pepper flakes if using. Cook 30–60 seconds until fragrant, not browned.
Add broth and chicken. Pour in the chicken broth and add the bay leaf.
Nestle the chicken into the pot. Bring to a gentle simmer.
Poach the chicken. Simmer on low, partially covered, for 12–15 minutes, or until the chicken is just cooked through. Remove chicken to a plate and let rest.
Cook the orzo. Add the orzo to the pot and simmer 7–9 minutes, stirring occasionally so it doesn’t stick.
Keep the heat at a steady but gentle bubble.
Shred the chicken. While the orzo cooks, shred the chicken with two forks into bite-sized pieces.
Add lemon and chicken back in. Stir in the shredded chicken, lemon zest, and the juice of 1 lemon. Taste the soup. Add more lemon if you want it brighter.
Season and finish. Remove the bay leaf.
Add chopped parsley or dill. Season with salt and black pepper. If you’d like, swirl in a splash of olive oil or sprinkle with Parmesan for a touch of richness.
Serve hot. Ladle into bowls.
Top with extra herbs, lemon wedges, and Parmesan if desired.