Place the chicken pieces in a large stockpot and add the cold water.
Bring to the boil, then reduce heat and simmer gently for about 3 hours.
Skim the stock well at regular intervals to remove any impurities from the surface.
Strain the stock carefully through a muslin- lined chinois or very fine strainer.
Discard the chicken pieces and allow the stock to cool.
Store in refrigerator and use as needed.
Discard after 3 or 4 days.
This stock can also be frozen.