Place chicken, onion, celery, carrots, garlic peppercorns and water into a large pot.
Cover with lid, leaving a slight gap to allow steam to release.
Bring to boil and then reduce temperature to a medium simmer. Cook for approximately 30 minutes.
Remove ingredients from pot, leaving soup water.
Remove any fat, veins or sinew from chicken and then shred meat.
Chop up vegetables and return to liquid along with the chicken (leaving out the garlic, peppercorns and onions if preferred).
Whilst preparing vegetables and meat, cook spaghetti pasta for time indicated on the packet. Make sure to place the lid on top off soup otherwise liquid may evaporate too much. If it does add a little more water.
With two minutes of pasta cooking time remaining, add the greens to the liquid to cook.
Season with salt to taste.