Cut the pork shoulder into 3-4 large chunks, just small enough to pick up with large tongs. Liberally season all sides of the pork pieces with the dry BBQ seasoning blend.
After 3 hours, remove the pork from the oven. Use tongs or a large slotted spoon to transfer the cooked pork to a large mixing bowl. Shred the pork using two forks or meat claws.
Use a slotted spoon to remove the cooked onions from the Dutch oven, then mix the onions into the shredded pork. Add as much braising liquid and pan juices to the shredded pork as you’d like. Extra juices will keep the meat juicy and tender.