Combine brine ingredients in a stock pot over medium high heat. Stir until brine just starts to boil and then remove from heat.
Once brine has cooled add chicken thighs and brine to a brine bucket.
After at least 12 hours in the brine, pull the chicken thighs out of the brine solution, pat them dry, and place them on a grilling rack.
Once all the chicken thighs are dried, generously sprinkle the rub on all sides of each thigh
Get your smoker up to 180 degrees and place your chicken thighs inside.
After an hour at 180 degrees, turn the heat up to 350 and cook for an additional 45 minutes to an hour. During the last 20 minutes of the cook, brush each thigh with your favorite BBQ sauce.
The thighs are done when the internal temp of the thickest part of each thigh is at 165 degrees.
Notes
Getting the outside of the chicken thighs dry before going in the smoker will help the skin have better bite once the thighs are done being cooked.