Puerto Rico claims pernil, a slow-roasted, marinated pork shoulder, as its own, and gives the dish pride of place for the Christmas Eve feast. However, numerous other countries across Latin America and the Spanish-speaking Caribbean promote their own version of the roast, which is surprisingly easy to cook. The key to pernil is voracious seasoning and a fierce final heat to crisp the joint’s skin.
Whereas pulled pork, a similarly indulgent roast, uses pork butt, pernil capitalizes on the thick skin layer and subcutaneous fat of the bone-in shoulder. In some places, this might be hard to come by and will have to be ordered from the butcher. Score the skin with a sharp knife to a depth of half an inch in a crosshatching pattern, and peel away the fat and skin layer but don’t separate it completely. Rub seasoning all over the skin, working it into the cuts, as well as beneath the loose skin layer, which can be laid back in its original position. Place the shoulder in a glass dish, cover with shrink-wrap and marinate overnight in the fridge. On roasting day, allow the shoulder to come back up to room temperature, and place skin-side up on a rack inside a high-sided roasting tray.
The traditional seasoning for pernil in Puerto Rico is sofrito, an all-purpose wet seasoning made from blended onions; Cubanelle green peppers; plenty of garlic, cilantro, hot bell pepper and salt; and a dash of vinegar. Other versions add cumin, chili and oregano. Because of the acid and salt, sofrito will keep in a sealed container in the refrigerator for weeks, and Puerto Rican kitchens typically have a ready chilled or frozen supply on hand. In a Cuban version, the marinating extends to dousing the shoulder in orange and lime juice for a citrusy aroma that combines with oregano and cumin. For a smoky, spicy skin, pernil asado calls for a drier rub of brown sugar, ground coffee, chili flakes, ginger and paprika.
Typically, the meat on a 4-pound shoulder falls off the bone after 3 hours at 300 degrees Fahrenheit, but 30 minutes per pound of pork is a reliable yardstick. The key to managing the shoulder’s moisture is to pour a cup of water into the roasting tray and to top it up regularly. Covering the joint with aluminum foil will seal in the steam, but doing so can leave the skin too soft to form the crisp skin called cueritos. Where rind is important, and it is de rigueur in the authentic pernil, cooks can either start with the shoulder uncovered and skin-side up for half an hour at 500 F, or save the intense heat for the last half hour. Once the internal temperature is 145 F the shoulder can come out the oven, but needs to rest covered for 30 minutes to seal in the juices.
Although the shoulder is prized as both a fatty and affordable pork cut, a fresh ham will suffice if shoulder is not available. Colombian-style pernil, for example, uses the leg, which can be marinated in beer, onion, garlic, cumin, pepper and achiote, a South American seasoning. Because it is less fatty, the leg needs regular basting during cooking with the juice that collects in the roasting tray. For cooks on a tighter schedule, a lean pork loin, rubbed in oregano, garlic and paprika, and roasted for an hour at 350 F, can possibly stand in. The sensory treat of tucking into chunks of oozing skin, however, is sacrificed for the shorter cooking time. At the other extreme, a marinated shoulder can go skin-side up into a slow cooker on low for 18 hours, turning halfway through.