Chop onion. Heat olive oil in large Dutch oven. Add onion and cook over medium heat, stirring occasionally.
Dice carrots and celery, add to the pot and continue to stir occasionally.
Add herbes de Provence and cook until vegetables are soft, stirring occasionally.
Stir in chicken stock, bring to boil and reduce to simmer.
Remove meat from chicken and shred or chop into bite-size pieces. Add to soup and simmer on low for 10 minutes, or until chicken is heated through. Season to taste with salt and pepper.
Notes
For chicken noodle soup, add zucchini noodles when you add the cooked chicken.