Season the chicken with salt, pepper, garlic powder, cover with water, and bring to a boil. Simmer until chicken is tender. Remove chicken from broth and debone. Save the broth!
Put carrots, onion, and celery in a big pot. Season with salt and pepper, cover with water, and bring to a boil.
Strain the broth, add to pot, and bring back to a simmer. Add the noodles and deboned chicken. Season to taste with salt, pepper, garlic powder, and parsley. Add additional water if necessary. Simmer till the veggies and noodles are tender. Serve with saltine crackers if desired.