Prep smoker temperature to 250°F, if not already in use. Clean off the grill grates of any debris.
Scrub, wash, and then dry the potatoes. Pierce with a fork, 5-6 times around the diameter.
Combine the butter and barbecue rub, mixing thoroughly. Brush the entire surface with half of the mixture.
Place the potatoes on the smoker, in indirect heat.
After 60 minutes of cooking time, brush with the remaining butter mixture. Smoke for another hour, or until tender enough.
Remove from the smoker.
Slice the tops open. Load up with desired toppings.
Serve and enjoy!