In a large saucepan over medium-low heat, bring the chicken stock to a simmer. Add the onion, carrots and celery and continue to simmer until the vegetables are slightly soft, about 10 minutes. Add the zucchini and 1 tablespoon of the parsley and cook until the zucchini is just tender, about 10 minutes longer

Add the noodles and simmer until they are just tender, 3-4 minutes, or according to the package directions.

Three minutes before the noodles are done, add the chicken and heat through. Season to taste with salt and pepper.

Ladle into warmed soup bowls and sprinkle the tops with the remaining 1 tablespoon parsley. Serve immediately.