Preheat the oven to 160/C325F/Gas 3.
Remove any giblets from the chicken carcass and place the chicken in a large saucepan or casserole dish. Add the carrot, onion, peppercorns, herbs, stock and white wine to the saucepan and bring up to the boil.
Season with salt and freshly ground black pepper, cover with the lid and place in the preheated oven to cook for 1½-2 hours or until the chicken is completely cooked. Test this by pulling the leg - if it feels as though it will come away from the carcass easily and the juices run clear when pierced, then it is ready. (For a larger chicken, cook for 20 minutes per 450g/1lb/ plus 30 minutes.)
Remove the chicken from the stock and place the chicken on a large clean plate. Remove all the meat from the carcass, discarding the skin and bones. Cut the chicken into strips approximately 1cm/½in wide and 5cm/2in long. Cover the meat and keep warm.
Remove the vegetables, peppercorns and herbs from the liquid in the saucepan and discard. Add the cream, bring up to the boil and cook uncovered for a few minutes. If the flavour
Is a little weak, boil until the taste becomes stronger. Season to taste with salt and freshly ground black pepper.
Whilst the liquid is still boiling, whisk in the roux - you need enough to thicken the mixture so it just about coats the back of a spoon.
Once the sauce is at the right consistency, place the chicken and any juices back in the saucepan. Season to taste with salt and freshly ground black pepper.
Serve with pilaff rice, mashed potatoes or boiled new potatoes and green salad with honey mustard dressing.