Sauté diced onion, sliced celery, and crushed garlic in 2 tbsp olive oil in a large soup pan over medium-high heat for 3-5 minutes until soft.

Add 8 cups gluten free chicken broth, 14.5 oz crushed fire roasted tomatoes, and 2 large chopped chicken breasts; stir well and heat until simmering.

Next, add 1.5 lb shredded cabbage, 0.5 teaspoon salt, and 1 teaspoon pepper. Add more chicken broth if the soup is too thick.

Cover and reduce the heat to medium-low, continuing to cook for 45 minutes.

Taste and adjust the seasoning as needed before serving.