In a small bowl, combine the last 9 ingredients (not including the buns!).
Sprinkle the onion slices on the bottom of the slow cooker. Place the pork roast on top.
Pour the sauce over the pork. Cook on high for 4 hours or on low about 7 to 8 hours.
Cool the pork and chill until ready to shred.
Take the pork out and shred it. I prefer to just shred it apart with my hands, this is why I wait until it is cold.
Return the pork to the sauce and mix together. Store in fridge. The longer it sits in the fridge, the better the flavors.
About a half hour before serving, reheat on the stove. Serve in the buns or biscuits with veggies.