1. Wash and pat dry the pork shoulder with a paper towel, place it on a plate.
2. In a bowl combine bbq rub, brown sugar and kosher salt.
3. Pat the dry rub on the meat on all sides.
4. Cover tightly with plastic wrap; place it in the refrigerator overnight.
5. Prepare a two foil ring by rolling it lengthwise; bring the ends together to form a circle.
6. Place the foil ring in the crockpot; add larger beer and place the pork in the center add the juice from the plate if any.
7. On low setting, cook the pork for 9-10 hours.
8. Once the internal temperature reaches 185 degrees the pork is done.
9. Remove the pork carefully from the crockpot and place it on a chopping board.
10. Remove the foil from the crockpot as well; pour the liquid into the fat separator, set aside.
11. Pour the defatted sauce in a sauce pan and reduces by 1 cup over medium high heat for 20 minutes.
12. Once the meat is cool enough to handle shred the meat with your hands, place the meat in a large bowl.
13. Once the sauce has reduced add cider vinegar, ketchup, brown sugar and liquid smoke.
14. Whisk and mix everything together.
15. Add some of the bbq sauce to the meat, toss at interval, add sauce as needed.
16. Fill the burger buns with bbq pork and serve the extra sauce on the side.
If you do not have the fat separator, then let the liquid settle for 5 minutes the fat will rise and you can remove it using a spoon.