Simply put, a porchetta roast is made by rubbing a butterflied pork roast with a flavourful mixture of herbs, spices, garlic and lemon zest, and then wrapping the whole thing up in a fresh pork belly. The whole thing is then slow-roasted for the better part of the day, until it’s juicy and falling-apart-tender, and then broiled until the exterior is crackling and golden-brown.