Boil the water in a wide cooking pot.
Put-in the chicken, carrots, celery, and onion. Simmer for 1 hour.
Remove the chicken and vegetables leaving the stock. Shred the meat of the chicken and discard the bones and then slice the carrots, celery, and onion.
Put everything back in the cooking pot along with the chicken stock and then apply heat.
Let the chicken stock re-boil (add a few cups of water, if necessary).
Add the rotini pasta. Cook for 15 minutes.
Transfer to individual bowls.
Serve. Share and enjoy!