Heat oil in a large dutch oven or stock pot over medium high heat. When oil it hot, add onion, carrots, celery, and cook for 3-4 minutes. Add garlic and cook another 60 seconds or so, being careful not to burn the garlic.
Pour in the chicken broth, chicken, and spices, and bring to a boil. Reduce heat to medium low and simmer for 15-20 minutes, or until chicken is fully cooked through. Remove chicken and set aside.
Add orzo to the pot and increase heat to medium high; cook for 8-10 minutes or until al dente.
Shred or dice chicken and add back to the pot, along with lemon juice, fresh spinach, and parsley. Adjust salt and pepper and serve!!