This is the juiciest pork loin ever. The secret lies in the acid from the tamarind and the slow braise
2 cups chicken broth1 tablespoon grated fresh horseradish, or 1 tablespoon prepared horseradishSeason the pork with the salt and pepper to taste. Let stand at room temperature for 15 to 30 minutes, to lose the cold from the refrigerator and for the salt to do its magic.Heat the oil in a 10-inch cast-iron skillet or a heavy-bottom sauté pan. Add the roast and sear on all sides, 15 to 20 minutes, until a dark golden crust forms.Remove the roast using tongs and transfer to a rimmed platter.
Cook until the alcohol evaporates, about 45 seconds. Add the tamarind paste, onions, chicken broth, and panela, and bring to a simmer. Return the pork to the pan. Carefully transfer the skillet to the preheated oven and roast for 40 to 50 minutes, until the internal temperature on a meat thermometer reaches 145°F.Remove the pork loin from the sauce and transfer to a rimmed serving platter. Tent with foil and allow to rest, for 10 to 15 minutes.