1. Place onions in stoneware. Combine brown sugar, paprika, salt and pepper; rub over roast. Place roast over onion

2. Combine vinegar, Worcestershire sauce, red pepper flakes, sugar, mustard, garlic salt and cayenne; stir to mix well. Drizzle about one third vinegar mixture over roast; cover and refrigerate remaining vinegar mixture.

3. Cover stoneware and cook on LOW 10 to 12 hours (HIGH 4 to 6 hours). Drizzle about 1/3 reserved vinegar mixture over roast during last half hour of cooking.

4. Remove meat and onions, drain. Chop or shred meat and chop onions. Serve meaet and onions on buns. If desired, top sandwiches wth coleslaw. Pass remaining vinegar mixture to drizzle over sandwiches.