Preheat the oven to 300ºF and pat the beef brisket dry with paper towels.
Evenly rub in the beef spice rub over all sides of the brisket.
Place the brisket in a 9”x13” baking dish and tightly cover it with foil. Bake the brisket in the preheated oven for 4 hours, or until fork tender.
When the brisket is done baking, mix together Stubb’s Original Bar-B-Q sauce, pineapple, Worcestershire sauce and chipotle in adobo. Pour the sauce over the baked brisket and return it to the oven to bake for 1 more hour.
Just before it’s finished cooking, turn the oven to broil. Broil the brisket just until the top begins to bubble and brown, about 5 minutes.
Then remove the brisket from the oven and carefully transfer it to a cutting board. Thinly slice the brisket against the grain.
Serve the thinly sliced brisket with the sauce from the pan and additional barbecue sauce