Preheat the oven to 170ºC/325ºF/Gas 3.  Heat 1 tbsp of oil with the butter in a casserole dish until hot. Toss the Diced Pork in a bag with the seasoned flour. Add to the pan and brown all over.  Remove with a slotted spoon. Add another tbsp of oil to the casserole dish and gently fry the onion, leek and garlic until soft.  Return the pork and add the white wine (or cider) and the hot stock, bringing to the boil and covering.  Place in the preheated oven for 1 hour, stirring once.

Remove from the oven and increase the oven temperature to 190ºC/375ºF/Gas 5.  Place the black pudding on the top, overlapping slightly. Brush the slices with olive oil and place back in the oven for 25 minutes until bubbling and crusty.