1. Preheat the oven to 200C/400F/gas mark 6. Carefully peel back the netting on the pork, if used, and pat the fat dry with kitchen paper.
2. Score the fat deeply with a sharp knife. Do not cut right down to the flesh, or the meat may become slightly dry during cooking. The closer together that you make the scores, the crisper and easier it will be to carve and serve the crackling. Ease the netting back over the meat to hold it together during cooking.
3. Place the prepared meat in a roasting tin and rub salt into the surface of the joint youll need about 1 tablespoon of salt for a 2.5kg joint.
4. Roast the pork in the bottom of the preheated oven. Calculate the cooking time by allowing 1 hour per kg, plus 35 minutes extra when roasting at 200C/400F/gas mark 6. If you prefer to roast slowly, allow 1 hour and 15 minutes per kg, plus 35 minutes extra at 180C/350F/gas mark 4 this is really more suitable for joints that will not yield good crackling.
5. Pour the sunflower oil into a roasting tin and heat it for 10 minutes at the top of the oven after the pork has been cooking for 1½ hours.
6. Peel the root vegetables and cut them into 4cm/2in pieces. Carefully turn the vegetables in the hot oil, then roast them at the top of the oven for 1½ hours, until browned and crisp. Turn them once or twice during cooking.
7. For the sauce, place the prepared cooking apples in a pan with the spices, lemon zest and juice and 300ml water. Cover the pan and stew the apples gently until they are soft.
8. Discard the spices pick them out of the sauce with a teaspoon then sweeten the sauce to taste with sugar. Put to one side until required.
9. Remove the pork from the roasting tin and wrap it in foil, then leave it to stand for 15-20 minutes before carving.
10. Drain off any surplus fat from the roasting tin, then stir the flour into the meat juices. Cook over a low heat for 1 minute, then gradually add the cider and the stock while it's off the heat. Bring the gravy to the boil gradually, then season to taste. Add a few drops of gravy browning if you wish.
11. Carve the pork and crackling so that its ready to serve at the same time as the roast root vegetables, gravy and spiced apple sauce. Also serve with a green vegetable such as Brussels sprouts or broccoli.