1. Trim off and discard any excess fat from the roast and place it in a 5-qt or larger slow cooker. Sprinkle the onion powder, garlic powder, salt, and black pepper over the roast and press the seasonings intot eh roast with your fingers. Pour the broth around the roast, taking care not to pour it over the meat. Peel and thinly slice the onion. Separate the slices into rings and add them to the pot. Cover the slow cooker and cook on low until the beef is fork-tender, 8 to 10 hours.
2. Turn off the slow cooker but leave the beef in the pot. Using two forks, carefully tear the beef into shreds. Stir the shredded beef well to mix it with the liquid in the pot. The cooled beef can be refrigerated or frozen for use in future recipes.
3. The average yield of shredded beef for a 4-1/4 pound roast is 8 cups, so there's plenty for several meals down the road. Here are some recipes that use Big Beef Roast: