You can halve this recipe, but chef Gerard Craft says he likes to make a lot so he has leftovers for sandwiches. We recommend ordering pork belly through an independent butcher, not a supermarket. The staff will be more accustomed to unexpected orders, and you're less likely to receive a rock-solid frozen belly. They may even remove the skin and trim the meat for you. Fennel seeds work, but look for fennel pollen, which has a sweeter and more intense flavor than fennel seed, at specialty stores or online.
Crispy skin is one of the pleasures of porchetta, but if you're squeamish about it (or can't be bothered with the prep), just order a skinless belly. You'll still be taking advantage of pork belly's richness and intense porky flavor.