Wash the turkey thoroughly with warm water (outside and inside)
Boil a pan of water with a couple of pinches of salt and add the chestnuts and bay leaf
Place the butter, crushed garlic, fresh rosemary and oil in a strong earthenware baking dish and place in the oven at 180 degrees
Meanwhile chop half of the boiled chestnuts and set the rest aside
Mix the chopped chestnuts with the sausages, chopped peach, chopped bacon, 1 tbsp port, a pinch of tarragon and salt and pepper and stuff the turkey with this mixture
Remove the baking dish from the oven and place the turkey on it - using a spoon make sure that it is well covered in the oil, butter and herbs in the dish
Cover the turkey in foil and place in the oven - after an hour remove it from the oven and take off the foil - pour the liquid in the baking dish over the turkey and return to the oven for another hour putting the small onions (cut into pieces) and whole chestnuts in the baking dish around it
Serve with freshly boiled vegetables such as carrots, broccoli or brussel sprouts.