Rub the brisket generously with spice blend, cover with plastic wrap and let marinate overnight in refrigerator.
Preheat the oven to 350 degrees F.
Put the roast, fat cap up, in a roasting pan. Add 1 cup water to the pan and roast the brisket uncovered for 1 hour.
In a medium bowl, combine the coffee, brown sugar, pepper, to taste, 3 cups hot water and cider vinegar.
Remove the brisket from the oven, pour the coffee mixture over the brisket, cover with foil and braise until brisket reaches an internal temperature of 185 and is fork tender, about 3 hours. Remove to a carving board to let rest.
Simmer the braising liquid in the roasting pan on the stovetop, skimming fat and allow to reduce just slightly or to desired consistency.
Thinly slice beef across the grain. Dip the meat slices or the cut sides of the rolls in the reduced sauce. Make sandwiches with the meat and serve. Pour the remaining sauce into a small bowl and serve it with the sandwiches.