After 6 hours of smoking, it is time to start layering the smoke flavors. Start by adding the apple wood soaked chips, a small handful at a time, every 20 minutes for an hour. Next, add the cherry wood chips in the same fashion as the apple wood. Finally, add the pecan wood chips following the same procedure. The cooking time should be about 9 hours at this point. Thereafter, any remaining wood chips can be mixed together and added every 20 minutes as before. This technique adds extra layers of smoke, creating a “smoke ring,” just under the skin, a true sign of good barbecue. The pork should be dark, almost black in color, and should nearly fall apart at the touch of a fork or knife. Remove the pork from the smoker and transfer it to a platter, letting it sit wrapped in foil for 20 – 30 minutes to redistribute the juices.