Place pork on a wire rack over the sink.

Pour over boiling water to scald the pork skin - this will help the skin crisp up into crunchy cracking. Pat rind thoroughly dry with kitchen paper and place pork uncovered in refrigerator for two hours.

Preheat oven to 220°C. Rub skin with oil and sea salt. Place pork onto a rack in a large, greased baking dish. Roast for 30 minutes.

Place vegetables into an ovenproof dish. drizzle over the oil and sprinkle with lemon zest and cumin to coat.

Reduce oven heat to 180°C. Add the vegetables and cook pork and vegetables for 60 minutes. Transfer pork and vegetables to a carving plate. Stand for 10 minutes.

Remove string from pork, slice and serve with roast vegetables and gravy.