Heat olive oil in a large soup pot over medium heat.
Add chopped onion and minced garlic.
Cook until the onion is soft.
Add chicken thighs to the pot.
Sauté for about 5 minutes until lightly browned.
Pour in the chicken broth.
Add cannellini beans, carrots, celery, salt, black pepper, and bay leaf.
Stir well.
Bring the mixture to a boil, then reduce the heat.
Cover and simmer for 30 minutes.
Remove the chicken.
Let cool slightly, then shred or cut into bite-sized pieces.
Return the chicken to the pot.
Continue simmering for another 10 minutes.