Preheat the oven to 220C/gas 7.
Heat a large frying pan over a medium-high heat. Add the chunks of belly, brown them well, then transfer them to a large, deep baking dish.
Pour off any excess fat from the frying pan, leaving a little behind. Brown the rabbit pieces in this fat. Do this in batches so that you don’t overcrowd the pan. Transfer the rabbit pieces to the baking dish, which should be big enough to hold all the meat in a single layer. Season all the meat generously with salt and pepper, and tuck in the whole sprigs of thyme, torn bay leaves, garlic bulbs and cloves. Sprinkle over the mixed spice and a good pinch of ground mace.
Deglaze the browning pan with the cider (pour the cider in, turn up the heat and let it bubble while you scrape up any bits of caramelised meat from the pan). Pour the liquid over the meat in the dish. Add the rendered pork fat and a glass of water. The liquid should almost cover the meat. Roast for 30 minutes in the hot oven, then turn it down to 140C/gas 1 and cook for a further 2½ hours, or until the meat is completely tender and can easily be pulled into shreds with a fork.
Remove from the oven and leave to cool a bit before pulling all the rabbit off the bones. Shred all the meat and place in a large bowl. Season with pepper, more mace, the chopped thyme leaves, some cayenne pepper and lemon juice.
Pour the cooking liquor into a jug and wait for the fat to separate before skimming it off. Reserve this. Pour the skimmed juices through a fine sieve on to the shredded meat. Add 2-3 tbsp of the reserved fat too, then give the whole thing a good mix.
Pack the mixture firmly into sterilised, sealable jars, making sure there are no air pockets. Top with a layer of the reserved fat before sealing the jars. Alternatively, fill the jars to the very rim, but don’t top with fat. Seal the jars, then put them in an oven preheated to 180C/gas 4 for 40 minutes to form a seal. Once cooled, the rillettes can be stored in the fridge for up to three weeks.
Serve with fresh crusty bread and something to cut the fat, such as cornichons.