In a small bowl, mix 1 tablespoon of the brown sugar, paprika, minced onion, chili powder, salt, garlic powder and allspice. Sprinkle 1 tablespoon of this mixture into the bottom of a slow cooker. Rub remaining mixture over pork. Add the vinegar and remaining brown sugar to the slow cooker; stir to mix. Add the pork.
Cover and cook on low 8 to 10 hours until the pork is fork-tender. Remove the pork to a cutting board and pull into shreds. Return to the slow cooker; add green onions and toss to coat.
Place about ¼ cup of the pork mixture onto each bun bottom. Add a sprinkle of hot sauce, if desired. Top with bun tops and serve immediately.
Notes
Use a slow-cooker liner to save on clean-up time (Reynolds makes them). Liners also make sure your meat is sealed in & moist and they prevent burning.