Muddle the fennel seeds and sea salt flakes. Score and generously cover both skin side and meat side of the pork belly in the salt. Rewrap and leave in the fridge either overnight or for an hour or so before cooking.
Allow your pork belly to come to room temperature, remove from fridge 20/30 minutes before cooking.
Preheat oven to 220 degrees Celsius.
Place pork in the oven, roast for 20 minutes or so until the skin blisters then lower temperature to 170 degrees and roast for a further 3.5-4hrs until the meat falls away from the bone.