In a large pot, heat olive oil over medium heat. Add diced onions and minced garlic, cook until translucent.

Add chicken breasts to the pot, cook until browned on both sides.

Pour in chicken broth, add sliced carrots, chopped celery, salt, and pepper. Bring to a boil.

Reduce heat, cover, and simmer for 20 minutes or until chicken is cooked through. Remove chicken, shred, and return to pot.

Taste and adjust seasoning as needed. Serve hot.