Preheat your smoker to 250°F using indirect heat. Place a water pan in the smoker to help maintain moisture and catch drippings.

Pat the pork belly pieces dry with paper towels. If using Costco pork belly strips, slice them crosswise into 1½ to 2-inch chunks.

Mix the rub ingredients in a small bowl. Coat each pork belly cube thoroughly on all sides.

Arrange the pork belly on a wire rack or directly on the smoker grates, leaving space between each piece for airflow.

Smoke for 2½ to 3 hours, or until a deep bark forms and the internal temperature reaches around 190°F.

Transfer the pork belly to a foil pan. Add the BBQ sauce, brown sugar, honey, and butter. Toss gently to coat.

Cover the pan with foil and return to the smoker for another 60 to 90 minutes, or until the pork reaches 200 to 205°F and becomes fall-apart tender.

Remove the foil and smoke uncovered for an additional 15 to 20 minutes to thicken the glaze, stirring once or twice as it caramelizes.

Let rest for 10 to 15 minutes before serving.