Heat olive oil in a large pot over medium heat.

Add diced onion and sauté until translucent.

Stir in minced garlic, carrots, and celery, cooking for 5 minutes.

Add cubed chicken breast, salt, and pepper, stirring to combine.

Pour in chicken broth and bring to a boil.

Stir in white rice and add the bay leaf.

Reduce heat to low, cover, and simmer for 20 minutes, or until rice is tender.

Remove the bay leaf and stir in fresh parsley.

Let the soup rest for 5 minutes before serving.

For extra flavor, you can add a squeeze of lemon juice just before serving.

Make sure to taste and adjust seasoning if needed, as the salt content of chicken broth can vary.

If you prefer a thicker soup, consider adding a slurry of cornstarch and water to the pot during the last few minutes of cooking.