Up to 2 days before, prepare the turkey. If you have a spice grinder or mini chopper, tip all the ingredients for the salt rub and grind to make a wet salt rub. If you are using a pestle & mortar, grind the spices and herbs together, then add the salt and orange rind and grind well again to combine. Carefully rinse the turkey and dry with kitchen paper. Sit it in a roasting tin and use the salt mix to season the turkey generously all over inside and out. Put the turkey, breast side up in the tin, cover with cling-film and leave in the fridge for up to 2 days. This can be done a day in advance but the longer you leave it, the more flavour the salt rub will permeate the turkey.
On the day you want to cook the turkey, remove from the fridge 1 hour before you want to cook it and rinse off all of the salt really well. Pat it dry, then rinse out the roasting tin and put the turkey back into the tin, again breast side up and leave at room temperature for 1 hour, uncovered.
To make the stuffing, melt the butter in a frying pan and add the onion and sage, then cook for a few minutes until the onion has softened but not coloured. Place the breadcrumbs in a bowl and tip in the onion mixture, then mix well to combine and season to taste and fold in the apricots, parsley and orange rind. Divide among two buttered sheets of tinfoil and roll each one into sausage shaped rolls, twisting the ends to fasten; set aside. These can be made 2-3 days in advance and kept in the fridge until needed.
Mix the butter with the Clementine rind and juice, sherry and sage and season with pepper and a little salt. Using a mini blender will make this job much easier. Rub all over the turkey inside and out and then stuff the halved orange into the cavity and tie the drumsticks together with string.
Preheat the oven to 190°C (375°F), Gas mark 5. Weigh the turkey to calculate the required cooking time, allowing 20 minutes per 450g (1lb) plus 20 minutes extra. Cover it with foil after about 45 minutes to 1 hour once you’ve achieved a good colour and baste every 45 minutes to 1 hour; it is important to do this quickly so as to not let the turkey or oven cool down, as this could alter the cooking time. Add the stuffing rolls to the turkey for the last 30 minutes and allow to finish cooking. If the stuffing rolls have been made in advance and are well chilled down then give them an extra 15 minutes or so until they are fully heated through. To be sure its cooked, insert a fine skewer into the thickest part of the thigh: the juices should run clear, but if they are still pink, return the turkey to the oven and check again every 15 minutes until you are happy that the turkey is cooked right the way through. Remove from the oven and transfer to a serving platter. Cover with foil and leave to rest in a warm place for 10 minutes or up to 30 minutes is fine.
Place the roasting tin directly on the hob over a gentle heat and skim any excess fat from the cooking juices. Stir the flour into the tin’s residue. Cook on the hob for a minute or two, stirring until golden. Pour in enough of the sherry to taste, stirring to combine, then gradually add the stock, stirring until smooth after each addition. Bring to the boil and let it bubble for about 10 minutes until reduced and thickened, stirring occasionally. Season to taste.