Prepare a grill for indirect heat: If you don’t have a smoker with an offset box, you can build a fire on one side of your grill and then put a piece of foil on the opposite side of the grill. This will create indirect heat.
Generously season ribs with the rub mixture, rubbing onto both sides of the rack. Place the ribs, meaty-side down and smoke for 3 hours at 225°. Wrap the ribs in foil and cook for 1 more hour. You’ll know the ribs are done when you try to pick them up in the middle and they fold down on either side.
Unwrap the ribs and baste them with a layer of barbecue sauce. Continue to smoke for 10 to 15 minutes to allow the sauce to caramelize. Pull ribs from the smoker and let them sit about 5 minutes before carving.
* To prep the ribs, remove the membrane from the back side of the rack. To do this, take a paring knife and slip the edge under the thin membrane layer. Use a paper towel to help pull it back off the ribs. Removing the tough membrane will help the smoke penetrate the meat and the rib meat to fall off the bones once they are smoked.