1 (4 to 5 pound) fresh beef brisket
1 (5 ounce) bottle liquid smoke
3 teaspoons garlic salt
2 teaspoons onion salt
2 teaspoons celery salt
1 (18 ounce) bottle barbecue sauce
Heavy-duty aluminium foil
Line a 12 x 9-inch or larger baking dish with heavy-duty aluminium foil, allowing enough foil to cover meat. Turn brisket fat-side down and pour entire bottle of Liquid Smoke over meat. Sprinkle the 3 salts over meat. Turn brisket over (fat side on top) and seal with foil. Marinate overnight.
Next morning pour off marinade; bake in a 225 degree F oven for 5 hours. Let cool.
Pour off gravy and refrigerate until cold. Slice meat with meat slicer on a thin setting or use an electric knife. Layer in casserole dish the brisket and barbecue sauce; repeat several times. Cook an additional 30 to 45 minutes in a 300 degree F oven until warm.