Pre-heat oven to 220°C.
Rub salt over the skin and roast the pork belly, skin side up for 30-40 minutes to crisp up into crackling.
Turn the oven down to 120°C and roast for a further 1 1/2 hours until very tender.
Meanwhile peel, quarter and de-seed the pears and cut them into chunks. In a saucepan over a medium heat, melt the butter, add the pears and caster sugar and cook until the pears become soft and start to stew. This will take around 25 minutes. If the mixture is still very chunky, mash with a fork to get a smoother consistency. Take off the heat and allow to cool.
Next, peel the black pudding and discard the skin. Cut into chunks and blend in a food processor until mixed but not pureed. Divide the mix into two and between two sheets of greaseproof paper roll each mix thinly into rectangles that will fit into an 20cm x 5cm rectangle tray. Place in the fridge to set, until it's needed.
Remove the pork from the oven and rest for 15 minutes.
Carefully peel or cut the crackling away from the meat and, if you can resist, put it to one side. Shred the boneless meat with two forks, the meat should resemble string and tear very easily. Season the meat, and add the chopped chives and leftover cooking fat from the pork, mixing thoroughly. In the bowl roughly divide into two and put to one side.
Line the tray with two layers of cling-film. Take one sheet of black pudding and lay in the bottom of the tin. Then take half of the pork belly mix and lay on top of the black pudding keeping as level as possible.
Next, spoon on the pear sauce, spreading evenly. Then add the second layer of pork belly and finish off with the final layer of black pudding.
Wrap tightly in cling film with a weight on top and rest in the fridge for four hours or overnight. Unwrap and cut into neat 5cm squares. You should end up with 20 even squares.
Flour, egg-wash and breadcrumb each cube, then egg-wash again and roll the cubes in porridge oats until completely covered.
Deep fry the cubes at 176°C for 4-5 minutes until crispy.