Pat the brisket dry with paper towels. Rub it all over with olive oil, then generously coat it with the dry rub, pressing the spices into the meat. Let it sit at room temperature for 30 minutes to allow the flavors to penetrate.
Bake Low and Slow
Preheat your oven to 275°F (135°C). Place the brisket in a roasting pan, fat side up, and pour the beef broth and apple cider vinegar into the pan to help keep it moist. Cover the pan tightly with foil and bake for about 5 hours, or until the internal temperature reaches 195°F (90°C).
Add the BBQ Glaze
Remove the foil and brush the brisket generously with the BBQ sauce glaze. Increase the oven temperature to 325°F (163°C) and bake uncovered for another 30-45 minutes, or until the sauce caramelizes.
Rest and Slice
Take the brisket out of the oven and let it rest for at least 30 minutes before slicing. This allows the juices to redistribute, making the meat extra tender. Slice against the grain for the best texture.