1. Preheat the oven to 160°C.
2. Cut the rind off the pork and score with a sharp knife and set aside.
3. Rub a little sea salt and freshly ground black pepper over the rolled pork and sprinkle with the dried thyme.
4. Heat the oil in a large flameproof casserole dish over a medium heat and brown the pork all over. Scatter over the leek and pour over the cider and stock. Stir in the sage, garlic, sliced apples and then tuck the herbs down under the liquid.
5. Bring it up to the boil, then cover and place in the oven for 4 hours, turning half-way through.
6. Take the rind and place on a baking sheet. Rub some salt into the skin and lay it skin side up. Place it into the oven and cook it for 4 hours.
7. After the 4 hours, remove the pork from the liquid, cover it with foil and leave it to rest somewhere warm for 20-30 minutes. Then remove the string and discard it.
8. Increase the oven temperature to 240°C and crisp up the crackling, this will take about 10-15 minutes.
9. Bring the pork cooking liqueur to the boil and reduce it by a third and season to taste. All the apples will be pulped down and flavours intensified. Skim off any fat that rises to the surface.
10. Slice the pork (it should just fall apart) and serve it with the cracking, and the apple gravy.
For the Potatoes:
1. Preheat the oven to 200°C, put the potatoes into a saucepan, adding just enough water to over them and add a pinch of salt.
2. Bring them to the boil with the lid off and when at the boil, reduce it to a simmer and cook for 2 minutes.
3. Drain them in a colander and return them to the pan, pop the lid on and give them a good shake.
4. In the meantime, put the fat and oil into the baking tin and heat in the oven until smoking hot. Remove them from the oven and place each potato in the fat. They should sizzle as they go in, if they don’t, place the tin back into the oven to heat up some more.
5. Roll each potato in the fat and make sure they are in a single layer. Place into the oven and cook for 15 minutes.
6. Remove, turn the potatoes over and then place back into the oven for another 15 minutes. Take out one more time and turn again and then place back into the oven for 10-15 minutes or until they are golden brown and crispy.
7. Remove and serve with a sprinkling of sea salt.