1Wrap the brisket entirely in bacon slices, and place into a large glass baking dish. Mix together the coffee and salt. Pour the coffee mixture over the brisket, cover, and marinate in the refrigerator overnight.
2In a saucepan over low heat, combine the butter and minced garlic. Cook stirring occasionally until butter is melted, and has turned golden. Spread all of the shortening onto the inside of a roasting pan. Place the brisket in the pan with one cup of the coffee marinade. Lay slices of the fatback over the roast. Place sweet potatoes around the perimeter of the roasting pan. Pour the garlic butter over the roast and potatoes. Let stand for 1 hour. Preheat the oven to 325 degrees F (165 degrees C)
3Cover the roasting pan with aluminum foil, and bake for 4 hours in the preheated oven. The internal temperature of the roast should be at least 145 degrees F (62 degrees C) when taken with a meat thermometer. Let stand for 10 minutes before slicing.
4While you wait for the roast, stir together the olive oil and horseradish in a small saucepan. Cook over low heat for at least half an hour, then pour into a small bowl. This is the dipping sauce for the brisket.