1Heat the olive oil in a large pot over medium heat.
Add the diced carrots and celery, and sauté for 4-5 minutes until they begin to soften.
Add the chicken breast to the pot and cook for 2-3 minutes, turning to lightly brown all sides.
Pour in the low-sodium chicken broth and add the dried thyme and salt.
Bring the mixture to a boil, then reduce the heat to low and simmer for 15-20 minutes, or until the chicken is cooked through.
Remove the chicken breast from the pot, shred it using two forks, and return the shredded chicken to the soup.
Add the fresh spinach and stir until wilted, about 1-2 minutes.
Taste and adjust seasoning if needed. Serve hot.