If your turkey comes with giblets, chop the liver very finely and saute in butter till just cooked. (If not, buy some frozen chicken livers, 3-4oz, 100-150g.) Mix that with the chestnut puree and roughly chopped whole chestnuts. Grate a medium onion and add that to the mix. Whizz up about 3 slices of white bread into crumbs, crusts too, chuck that in and season well with salt, pepper and half a teaspoon of sugar and stuff bird. I always stuff the body cavity with this and the neck end with herby, apricotty, sausagey stuffing but I know were not supposed to stuff the body cavity - I'm still here, as are my family and I've never poisoned any of them!