Generously rub the BBQ seasoning all over the pork.

Heat a pan over high heat. Sear all sides of the pork shoulder for 2 minutes each.

Place the pork in a slow cooker, on top of the sliced onion. Pour the BBQ sauce over and cover the slow cooker and turn on low.

Cook for 6-8 hours - at this point the pork will be fall apart tender. Use tongs to place the pork in a bowl. I poured the sauce (including the onions) into a large saucepan and thickened it letting it reduce by one third. Use two forks to shred the pork and stir in the BBQ sauce.

Place about ½ cup of the shredded pork on a bun, and add any toppings you like.