In some of my recipes, I season the pork the day before cooking so that the seasoning can penetrate. In others, I braise it the day before serving, because everything braised is better the second day. Cook times are long, too, to break down all the connective tissue in the meaty part of the belly and melt the fat so that the whole thing is tender enough to give at the mere sight of a fork.
I have several methods for cooking pork belly. I often like to use a rub that has sugar in it, and then roast it so the dry heat caramelizes the sugar on the surface. Other times, I’ll give it a quick sear to enhance the pork flavor, then braise it in a really flavorful liquid to break it down into silky luxuriousness. I love pork belly with the skin on, too, for a crunchy pop. When I’m cooking it skin on, I simmer the belly in water so that the meat and fat get the tender quality that comes with wet cooking; then I broil it skin side up before serving to puff and crisp it.