Place chicken in a large pot, cover with chicken stock and 2 quarts of water

Add onion quarters, roughly chopped carrots, celery and parsley stems

Bring to a boil, partially cover and reduce heat to simmer. Simmer for 1 hour, chicken should easily pull from bone

Remove chicken and cool; strain cooking liquid, discard vegetables and reserve stock. Shred chicken

Melt butter in crockpot over medium-high heat, add diced onions, carrots and celery. Cook until vegetables till softened, about 2 minutes. Stir in cooked chicken and chicken stock and bring to boil over high heat

Season soup with salt and pepper

Add noodles and simmer till cooked. Approx 10-12 minutes

Add parsley and serve