Place pork butt in shallow glass pan. Rub the surface of the pork with the glazing rub, drizzle with olive oil and rub again. Cover and refrigerate overnight. Preheat one side of the charcoal grill to medium. Drain the apple chips and place in the wood chip tray on the hot side of the grill. Keep the other half of the grill on very low heat. Place the pork on the lower heat side of the grill and cover with lid. Cook slowly at about 300° F, until meat is tender and falling off the bone, about 3 hours. Turn meat every 30 minutes. Remove from grill and let rest for 10 minutes. Shred into bite size pieces and place in large bowl. Toss with BBQ sauce, place on buns and top with sliced red onion.
Barbecue Sauce: Mix 1 cup Mansmith’s Barbecue Paste with 1 cup apple cider vinegar, 1/2 cup apple juice and 2 Tbsp. brown sugar. Bring to a boil and remove from heat.