In a medium bowl, mix brown sugar, tomato paste, apple cider vinegar, chili powder, dry mustard, Worcestershire sauce, and smoked paprika until well blended.

Stir in onion and pepper.

Place half of your mixture in the bottom of a 6-8 quart slow cooker.

Place your pork shoulder roast over the mixture and pure the remaining mixture over it.

Set your slow cooker on low for 8-10 hours.

Using 2 forks or a meat shredding tool, shred the pork shoulder into thin sections.

Serve by itself or on a bun warm with barbecue sauce.