Preheat oven to 425°F. Line a baking sheet with aluminum foil. Trim brisket of excess fat. Evenly sprinkle barbecue seasoning, salt, and black pepper over the entire surface, pressing firmly. Place on the prepared baking sheet, and bake uncovered 30 minutes.
To a Crockpot, whisk together broth, ½ cup of the barbecue sauce, Worcestershire sauce, soy sauce, and liquid smoke.
Transfer the brisket to the Crockpot, cover, and cook on low for 7-8 hours.
Pierce with a fork, and if the brisket doesn’t have a tender pull, cook an additional 1-2 hours.
Preheat the oven to broil. Line a baking sheet with aluminum foil, and transfer the cooked brisket to the pan. Brush with ¼ cup of the barbecue sauce on top, and broil 3-5 minutes or to when the edges start to darken and become crispy. Gently flip the brisket, brush with remaining ¼ cup barbecue sauce, and broil 3-5 additional minutes. Watch it carefully as some barbecue sauces can burn quickly.
Transfer brisket to a cutting board, rest 5 minutes, then slice against the grain or chop. Place it back in the crockpot. Serve with additional barbecue sauce and your favorite sides.