Prep the Pork: Start by removing excess moisture from the pork belly with paper towels, then trim any remaining thick fat from the outside.
Cut the pork belly into 1-inch cubes and season with salt and black pepper. Let it sit in the refrigerator for 60 minutes to allow the salt to draw out moisture, then pat dry again with paper towels.
Marinade: In a mixing bowl, whisk together the soy sauce, lime juice, brown sugar, water, minced garlic, and black pepper until well combined.
Place the pork belly cubes in ziplock bags and pour the marinade over them, tossing to ensure even coating. Seal the bags and refrigerate for at least 4 hours, or up to 24 hours for deeper flavor.
Load your Traeger with cherry wood pellets and set the temperature to 225°F, waiting for it to reach the target temperature.
Place the marinated pork belly pieces directly on the grill grates and insert a temperature probe into the largest cube. Close the lid and smoke for 3 hours, maintaining consistent temperature throughout.
While the pork is smoking, prepare the glaze by whisking together brown sugar, honey, soy sauce, lime juice, and water in a saucepan over medium heat. Bring the mixture to a boil, then reduce to low heat and simmer until it thickens slightly, about 5 minutes. Remove from heat and set aside until ready to use.
Increase your Traeger temperature to 275°F and remove the smoked pork belly to a foil pan or baking tray. Cover the pork with the prepared glaze and toss to coat evenly.
Cover the tray with foil and return to the smoker for 45 minutes, then remove the foil and continue cooking for another 15 minutes until the pork develops a deep, dark color. Let the pork belly rest on a wire rack for 10 minutes, covered with foil to allow excess fat to drain.