Heat olive oil in a Dutch oven, cook carrots, onion, and celery for about 5 minutes.
Add garlic and cook for 30 seconds, then stir in Italian seasoning, salt, and pepper; cook for 2-3 minutes.
Puree half of the beans with 1 cup of chicken broth, then add to the pot with remaining beans, broth, and chicken. Cover and simmer for 20-30 minutes until chicken is cooked and shredded.
Shred the cooked chicken, return to the pot, then stir in spinach, lemon juice, and parsley. Simmer for 5 minutes until spinach wilts.
Notes
For extra flavor, add a squeeze of lemon just before serving.