First of all, you need to insert the cloves and ginger into the pork, so begin by peeling the ginger then cutting it into little strips vaguely half the size of matchsticks. Then take your smallest, sharpest-pointed knife and begin to make slits in between the pork rind and right down into the flesh, then push a piece of ginger into each slit as you make it. When half the ginger has been inserted, turn the joint upside down and do the same on the other side, sliding the knife in between the bones and again trying to get the ginger well into the flesh of the pork.
After that, insert the cloves here and there in both sides, pushing these well into the same little slits. Just before cooking the pork, sprinkle the rind with salt and black pepper, being quite generous and pressing it well in all over. The golden rule for crunchy crackling is a) not to use too deep a roasting tin as this creates too much steam, and b) to keep the rind of the pork well up from the sides of the tin – this can be achieved by using a roasting rack or, failing that, take a very large piece of foil and crumple it to make yourself a roasting rack to sit the pork on top.
Then put a couple of onion halves in the tin as these will caramelise and give a lovely flavour to the gravy. Now place the pork on a high shelf in the oven. Give it 20 minutes' initial cooking time, then turn the heat down to gas mark 5, 375°F (190°C) and give the pork another 2 hours' cooking. Don't baste it at all, just leave the rind to get really blistered and crisp. About 20 minutes before the end of the pork cooking time, make the purée of apples and ginger. Start by melting the butter in a medium saucepan over a gentle heat and soften the onion in it for about 5 minutes.
Meanwhile peel, core and thinly slice the apples and when the onion is soft add them to the pan, followed by all the rest of the ingredients. Season, then, keeping the heat low, cover with a lid and cook everything very gently for about 20 minutes, stirring now and then. When the apples are soft and fluffy, beat them with an electric hand whisk or a balloon whisk until they form a soft, smooth purée. Pour the purée into a warm serving bowl and keep warm till you're ready to serve the pork.
Then, 5 minutes before the cooking time for the pork is up, increase the oven temperature to gas mark 7, 425°F (220°C). Mix together the honey and ground ginger, then remove the pork from the oven and quickly paint this all over the rind with a brush.
Then back it goes into the oven for a further 5 minutes' cooking time – please use a timer as at this temperature it can burn if you forget! After that, remove the pork from the oven, transfer it to a carving board and let it relax in a warm place for 30 minutes before carving. Make the gravy by spooning the excess fat from the roasting tin, leaving about 1½ tablespoons behind. Then place the tin over a direct heat and sprinkle in the flour, stirring vigorously with a wooden spoon, scraping the base and sides of the tin to remove all the crusty bits.
When it's really smooth, begin to add the cider a little at a time, switching to a balloon whisk to whisk everything smoothly. There won't be enough liquid now, so finish it off using some of the vegetable stock, or cooking water from vegetables, adding as much as you need to make the consistency you want. Let it bubble for a minute, taste to check the seasoning and then pour it into a warm serving jug. You can then remove the onion, or not.
To carve the pork, simply slide the knife all the way along the central bone to remove it. Then remove the rib bones, which will come away in one piece. The pork will then be ready to carve in even slices.