1 C Chipotle-Maple Barbecue Sauce, plus more for serving (see next recipe)
1 C beer
Place the beef in a baking dish and sprinkle it with Rub.
Stir the sugar, Worcestershire sauce, and vinegar together in a small bowl and pour it over the brisket, turning it several times to coat it evenly on all sides. Cover and marinate in the refrigerator for at least 6 hours or overnight.
Preheat the oven to 350° F (176°C) or prepare a hot fire in a charcoal or gas grill.
Allow the brisket to sit out to room temperature.
Transfer the brisket to a plate, allowing any excess marinade to drip back into the baking dish. Reserve the marinade. Transfer the brisket to the grill or grill pan and cook, turning only once, until slightly charred but not cooked through, 4 to 6 minutes per side.
Place the seared brisket in a large cast-iron or other ovenproof skillet and pour the reserved marinade over it.
Stir the barbecue sauce and beer together in a small bowl and pour it over the brisket, turning it several times to coat it evenly on all sides.
Cover the skillet with aluminum foil or a tight-fitting lid and roast the brisket for 3 to 3 1/2 hours, until it pulls apart easily with a fork.
Remove the brisket from the oven and let cool slightly. Transfer the brisket to a rimmed cutting board and thinly slice across the grain or use two forks to shred it.
Serve the brisket warm, with additional warm barbecue sauce drizzled over the top or served on the table.