This recipe is inspired by the Korean dish bossam, which translates to “meat and other fillings wrapped in leafy vegetables.”
Place the pork in a large bowl or baking dish. Combine the granulated sugar and salt in a small bowl and then rub all over the meat and in the folds. Cover with plastic wrap and refrigerate for at least 8 hours and up to 24 hours, turning once or twice.
Thirty minutes before grilling, remove the pork from the bowl and discard the accumulated juices. Blot the meat dry with paper towels and place in a heavy-duty roasting pan. Let stand at room temperature while you prepare the grill.
Prepare the grill for indirect cooking over low heat (250° to 300°F).
Place a large foil pan on top of the Flavorizer bars, below the cooking grate. Fill it halfway with room temperature water. Prepare the grill for cooking over low heat (275°F).
Grill the pork over indirect low heat, with the lid closed, until an instant-read thermometer inserted in the thickest part of the pork registers 195° to 200°F and the meat is fork-tender, 5 to 7 hours, turning and basting occasionally with the pan juices.
Grill the pork above foil pan, over low heat, with the lid closed, until the thickest part of the pork registers 195° to 200°F and the meat is fork-tender, 5 to 7 hours, turning and basting occasionally with the pan juices.
While the meat is roasting, combine all of the ingredients for the ginger-scallion sauce in a bowl and mix to blend. Refrigerate until use.
In a separate bowl whisk all of the ingredients for the chili sauce.
Remove the meat from the grill and transfer indoors to a cutting board. Pour off and reserve the accumulated fat and juices. Let the pork stand indoors until cool enough to shred.
Prepare the grill for indirect cooking over high heat (450° to 550°F).
Keep the large foil pan on top of the Flavorizer bars, below the cooking grate, filled with water. Prepare the grill for cooking over high heat (500°F).
Shred the pork and return to the roasting pan. Drizzle 3 to 4 tablespoons of the reserved fat over the meat to moisten and lightly coat. Sprinkle the brown sugar over the pork. Transfer to the grill and cook overindirect high heat, with the lid closed, until the meat begins to crisp and caramelize in parts, 8 to 10 minutes. Remove from the grill and transfer the meat to a serving platter.
Shred the pork and return to the roasting pan. Drizzle 3 to 4 tablespoons of the reserved fat over the meat to moisten and lightly coat. Sprinkle the brown sugar over the pork. Transfer to the grill above foil pan, and cook over high heat, with the lid closed, until the meat begins to crisp and caramelize in parts, 8 to 10 minutes. Remove from the grill and transfer the meat to a serving platter.
Serve with the lettuce leaves, rice, ginger-scallion relish, red chile sauce, cilantro, and sesame seeds.