Preheat your oven to 300 degrees Fahrenheit.
In a large bowl, combine the garlic powder, onion powder, smoked paprika, black pepper and cumin.
Rub the spice mixture all over the brisket.
Place the brisket in a roasting pan and cover with BBQ sauce.
Bake in the oven for 3 hours or until the brisket is very tender.
Remove from the oven and let cool slightly before slicing into thin slices.
Serve with your favorite sides!