Heat oven to 220C/200C fan/gas 7. Tip the onion into a roasting tin and put the pork shoulder on top. Rub the pork skin with the oil and sprinkle with salt and the fennel seeds, if using. Tuck the garlic cloves under the side of the pork. Roast for 30 mins or until the skin begins to crackle up, blister and brown.

Reduce heat to 180C/160C fan/gas 3, add the apples to the tin, and roast for about 2 hrs or until the meat is very tender when tested with a sharp knife. Lift the pork out to rest and spoon out the apple and onion.

While the pork rests, make the gravy. Tip all the fat out of the tin, then put it over a low heat. Add a splash of stock, scraping any sticky bits off the bottom with a wooden spoon. Pour in the remaining stock, then bring everything to the boil. Squash in the garlic and remove the skin. Strain the gravy through a sieve into a jug. Serve the pork and crackling in slices with the roasted apple, onion and gravy, and either roast or mashed potatoes.