Make sure you have extra buns on hand because people will be going back for more. Excellent the next day for leftovers. Serve with your favorite coleslaw recipe.
Stir celery, onion, barbeque sauce, ketchup, water, garlic powder, chili powder, salt, and pepper together in a slow cooker. Place roast into the mixture.
Cook on Low for 7 hours (or High for 5 hours). Shred the meat with two forks and stir into the liquid; cook for 1 hour more.
Per Serving: 323 calories; protein 26.3g; carbohydrates 22.8g; fat 13.8g; cholesterol 89.4mg; sodium 787.4mg.