Sauté the aromatics: Heat olive oil in a large pot over medium heat. Add the onion, garlic, carrots, and celery. Cook until softened, about 5–7 minutes.
Add the chicken and herbs: Place the chicken in the pot with the vegetables. Sprinkle in oregano, thyme, bay leaf, salt, and pepper.
Pour in the broth: Add chicken broth and bring to a boil. Reduce heat, cover, and let simmer for 25–30 minutes until the chicken is tender.
Shred the chicken: Remove the chicken from the pot, shred it using two forks, and return it to the broth.
Add the pasta: Stir in the pasta and cook until al dente, about 8–10 minutes.
Finish with flavor: Stir in lemon juice and parmesan cheese. Taste and adjust seasoning.
Serve: Ladle into bowls, top with parsley, and enjoy warm.