Pork belly might be the ingredient-in-vogue in trendy, posh restaurants, especially those that specialize in nose-to-tail utilization of the pig, but its humble delectability is timeless. From porchetta to cracklings, pork belly satisfies the appetites of casual foodies and world-class gourmands alike. Like other simple, honest, rustic foods, pork belly does well with a wide array of cooking methods, with slow roasting performing something akin to magic on this magical meat. Spiced-and-slow-roasted pork belly undergoes a true melding of flavors in the low oven, where it's subjected to hours of spicy penetration and smooth rendering of its luscious fat and juices.
Remove the pork belly from the refrigerator about one hour before you roast it and place it on a plate and let it reach room temperature. Heat the oven to 450 degrees Fahrenheit.
Pat the pork belly dry with paper towels. Score the skin of the pork belly in a crosshatch pattern, taking care not to cut into the meat -- just the skin. Scoring prevents curling during cooking and makes an attractive pattern. Make the slices about 1/2 inch apart.
Rub a 2:1 ratio of kosher salt to baking soda over the skin of the pork belly. The salt draws out moisture to help it dry, and baking soda helps the skin crisp. You need about 2 teaspoons of kosher salt to 1 teaspoon of baking soda for every pound of pork.
Create a spice rub or paste for the pork belly. When it comes to spicing, you're the artist, the pork belly is your canvas, and every spice comprises your palette. Pork belly is fatty and bold in flavor, so it goes well with aggressive spices, such as smoked paprika, chili flakes, cracked peppercorns, spicy harissa and fresh garlic paste, to name a few. It also pairs well with softer spices, such as fennel seeds, fresh rosemary and fresh thyme.
Season the bottom and sides of the pork belly to taste with kosher salt and add your spices. You don't have to salt the skin again.
Slather the pork on all sides with a coating of oil and place it on a wire rack in a roasting pan, which allows hot air to circulate underneath the pork and cook it uniformly. Place the pork belly in the oven.
Roast the pork at 450 F for about 15 minutes. The initial high heat gives the skin a crisp texture and golden-brown color. Continue to roast the pork at 150 F for about four or five hours, or until you can tear the meat from the belly with little effort. Remove the pork belly from the oven for serving.
Buy the freshest, leanest, center-cut, skin-on pork belly from a heritage pig raised by a reputable organic farmer for the best results. If you can't find an organic farmer who sells heritage pigs, just buy the freshest, high-quality pork belly from a local market.
If you want to add even more texture and complexity of flavor to the pork belly, let the cooked belly chill in the fridge overnight so the flavors meld. The next day, cut the belly into portions and fry it until crisp in a heavy-bottomed frying pan.