Heat olive oil in a large pot over medium heat. Add onion, carrots, and celery, and cook for 5-6 minutes until vegetables are softened.
Add minced garlic and cook for 1 minute until fragrant.
Pour in chicken broth and bring to a boil. Add orzo pasta and cook for 8-9 minutes until orzo is tender.
Stir in shredded rotisserie chicken and cook for 2-3 minutes until heated through.
Remove from heat and stir in lemon juice, lemon zest, and fresh parsley. Season with salt and pepper to taste.
Serve hot with additional lemon wedges on the side if desired.