For Christmas turkey, you will need:

1 fresh turkey, giblets removed and set aside
Softened butter

For the stuffing (enough for a 15lb / 6.75kg turkey):

1 kg sausage meat
8 tbsp wholemeal breadcrumbs
2 sticks of celery, finely chopped
6 shallots, finely chopped
2 oz / 60g chopped almonds
Juice and zest of 1 orange
2 tbsp finely chopped thyme
3 tbsp finely chopped parsley
2 tsp ground allspice

For the gravy:
Giblets from the turkey
2 rashers bacon, lightly fried and chopped
1 onion, peeled, chopped and lightly fried
1 carrot, peeled and cut into large chunks
1 stick of celery, chopped
1 bouquet garni
2 tbsp plain flour
½ oz / 15g butter
½ tsp ground black pepper
2 tbsp Marsala
1 tsp salt
Oil for frying
water

The day before cooking the Christmas turkey, mix together all the ingredients for the stuffing in a large bowl, cover and place in a refrigerator for the flavors to develop.
Remove the turkey and the stuffing from the refrigerator 1 hour or longer before cooking, depending on weight, to allow it to get to room temperature at the start of the cooking time (cooking time will need to be increased if the bird is colder than room temperature). Rinse the inside and outside of the turkey under cold water and blot dry. Stuff the cavity with the prepared stuffing. Weigh the stuffed bird and work out the cooking time according to the combined weight of the bird and stuffing.
Rub some butter over the turkey breast. Place the bird in a large roasting tray with the breast side facing down. Bake in a preheated oven at 200°C (400°F) for 30 minutes. Turn down to 180°C (350°F) for the remainder of the cooking time (see below). During this time, baste the bird two or three times with any juices in the tray. Turn the bird the other way up for the last 30 minutes of cooking time in order to brown the other side. Consult a meat thermometer to check the bird is cooked. If you do not have a meat thermometer, insert a skewer into the thickest part of the turkey, usually just behind the thigh. If the juices run clear the bird is cooked. Set aside to rest for about half and hour before carving.

To make the gravy for the Christmas turkey, lightly fry the liver and set aside. Place the rest of the giblets, bouquet garni, black pepper, bacon, onion, carrot, celery in a pan filled with 1.3quart / 1.5 liter / 50 fl oz water. Bring to boil, turn down heat and simmer for 2 hours. Discard the bouquet garni from the stock. Add the stock to the juice in the turkey tin, after first skimming off any excess fat from the juice. Mix the flour in the Marsala and a little cold water and add to the mixture. Stir well. Transfer to blender, add the liver and blend until smooth. Transfer to a small saucepan and bring back to boil, stirring from time to time. Serve.

Christmas turkey cooking times:

5lb / 2.25kg, cook for 200°C (400°F) for 30 minutes, then 1 ½ hours at 180°C (350°F)
7lb / 3.5kg, cook for 200°C (400°F) for 30 minutes, then 1 ¾ hours at 180°C (350°F)
10lb / 4.5kg, cook for 200°C (400°F) for 30 minutes, then 2 hours at 180°C (350°F)
12lb / 5.5kg, cook for 200°C (400°F) for 30 minutes, then 2 ½ hours at 180°C (350°F)
15lb / 6.75kg, cook for 200°C (400°F) for 30 minutes, then 2 ¾ hours at 180°C (350°F)
16lb / 7.5kg, cook for 200°C (400°F) for 30 minutes, then 3 hours at 180°C (350°F)
20lb / 9kg, cook for 200°C (400°F) for 30 minutes, then 3 ½ hours at 180°C (350°F)
25lb / 11.5kg, cook for 200°C (400°F) for 30 minutes, then 4 ½ hours at 180°C (350°F)