Prepare the brine according to directions. Brine the chicken for 1 1/2-2 hours in your refrigerator.
Remove the chicken from the brine solution, and blot dry with paper towels. Set them, skin side up, onto a clean plate or small baking dish. Place them into your refrigerator uncovered for 2 hours to air dry. Once the chicken skin looks shiny, it's good to go.
Preheat your smoker or grill to 250 degrees F. Add wood according to the manufacturer's directions.
Trim the chicken thigh skin to form a square patch covering the meat. Please note that the skin should still be attached on one side! Remove excess fat around the edges as well.
Apply the BBQ rub evenly on both sides of each thigh and under the skin.
Once your smoker is up to temperature, place the chicken thigh on the grill, skin side up. Close the lid, and let them cook until they reach an internal temperature of 165, about 1-1 1/2 hours.
Once they reach 165 degrees, remove your smoked chicken thighs and place them onto a heat-safe wire rack or clean cutting board. Brush a liberal amount of BBQ sauce on them. Place the thighs back on the grill. Close the lid, and let them cook for another 30 minutes or until they reach an internal temperature of 175-180 degrees F and the sauce has caramelized
Remove the chicken from the grill, and place them on a clean cutting board or platter. Let them rest for 10-15 minutes, and serve.
Store your smoked chicken thighs in an airtight container in the refrigerator for 3-4 days. Rewarm in a 325-degree oven until they reach an internal temperature 165 degrees F.