Preheat oven to 200°C (use the fan setting if your oven has it, or fan-grill.)
Spread the chicken joints, skin side up, on a rack set over a roasting tin or high-sided baking tray. Roast for 30 minutes until the skin is crisp and golden, then turn and cook for a further 10 minutes to brown the underside.
When cool enough to handle, remove the skin from the chicken — delicious as it is, the skin is where most of the calories and saturated fat sits. Pour the fat off the tin and discard, but leave the delicious, flavour-packed residue (the fond) at the bottom of the roasting tin.
Put the chicken, vegetables and turmeric into a large soup pan and saute over medium heat for 5-10 minutes.
Add the water, salt, parsley and the fond, which will by now have formed a film that can be easily be removed from the tin. Cover and simmer for 3 hours, either on top of the stove or in the oven at 150°C.
Leave to cool, then remove the chicken pieces. Use these off the bone for pulled chicken, Caesar salad, wraps, pies or add to your finished soup.
Strain the stock into a large container and refrigerate overnight. The next day return the stock to the pan with the young carrots, leeks, celery and stock cube. Simmer, uncovered, until the vegetables are tender, about 15 minutes.