Heat oil in a large pot over medium-high heat. Sauté celery, onion, and garlic for 3-5 minutes or until soft.
Add broth. Bring to a boil.
Add Italian seasoning, herbs, and sweet potatoes. Reduce heat and simmer for 20 minutes.
Add green beans, zucchini, white beans, and chicken.
Simmer 15 minutes. Add sea salt if desired.
Ladle stew into bowls and serve hot.