1. Get the skin of the pork neatly scored and have any lumps of excess fat removed from underneath by the butcher to keep the joint flat.
2. Place the pork into a shallow dish skin side up and sprinkle over some salt.
3. Rub it into the pork and put it aside for about 45 minutes so that it will help to pull out any excess water from the pork.
4. After about 45 minutes, mop up any water from the joint using a clean cloth or a sheet or two of kitchen paper.
5. Peel and cut the onion into thick slices.
6. Wash, peel and rewash the carrots and cut into slices.
7. Wash the celery and chop into largish slices.
8. Wash the apple, remove the core (no need to peel) and cut into largish wedges.
9. Wash the thyme and sage.
10. Mix these ingredients together and lay into a roasting tray.
11. Lay the belly pork joint on top skin side up.
12. Pour over the oil and season with salt and pepper.
13. Pre-heat the oven to 170°C (Gas Mark 3).
14. Make the apple sauce.
15. Put the pork into the pre-heated oven and allow to roast slowly for about 1½ hours.
16. Then, turn up the temperature to about 190°C (Gas Mark 5) for a further 30–40 minutes.
17. Remove the pork from the oven and place the joint onto your board.
18. Carefully remove the crackling (it should come away quite easily).
19. Cover the joint with tin foil and allow it to rest for 10 minutes, but keep it warm.
20. Break the crackling into smaller pieces.
21. Place the pork onto your board once again.
22. Using a sharp knife, carve it into slices and neatly place onto warmed plates.
23. Garnish with pieces of crackling and warm apple sauce and serve.