Trim roast of visible fat. Sprinkle with salt, pepper and garlic powder and rub into the meat. For optional browning, heat 1 tablespoon olive oil in a large nonstick skillet over medium heat until hot. Brown the roast on all sides, approximately 2 minutes per side. Add roast to a 3 to 5 quart slow cooker. Cover beef with barbecue sauce. Add onion. Cover and cook on low 9 to 10 hours or on high 5 to 6 hours until roast is fork tender. Remove roast and onions from slow cooker. Shred beef with 2 forks. Serve on fresh kaiser rolls from the Bakery, a side of cole slaw completes a delicious meal.