Using a sharp knife, trim off as much fat as you can from the brisket and set aside.
In a small mixing bowl, combine together the pepper, salt, onion powder minced garlic and liquid smoke to create a wet spice rub.
Lay out a sheet of aluminum foil and place brisket on the foil, rub the spice mixture into the meat on all sides.
Bring up the sides of the foil and wrap the brisket in the foil so that the juices from the meat do not escape while cooking.
Wrap meat with another layer of foil so that you have a double wrapped foil packet.
Place foil packet in the bottom of a 6 quart or larger slow cooker.
Cover and cook on LOW for 8 to 10 hours.
Carefully remove foil packet from slow cooker and unwrap meat. Baste the meat with the juices and allow the meat to rest for 10 minutes before slicing and serving.