Pat the chuck roast dry
Season all sides with salt, pepper, garlic powder, and onion powder
Optional: sear the roast in a hot skillet until browned on all sides
Place sliced onions, carrots, and potatoes in the slow cooker
Put the chuck roast on top of the vegetables
Add beef broth, Worcestershire sauce, and optional tomato paste
Add garlic, thyme, rosemary, or bay leaves if desired
Cover and cook on low for 8 to 10 hours or on high for 4 to 6 hours
Cook until the roast is fork-tender
Remove the roast and vegetables from the slow cooker
Shred or slice the roast
Skim excess fat from the cooking liquid if desired
Serve with the vegetables and spoon the juices over the meat