Place 5 to 10 pound brisket, fat side up on a large sheet of foil or a baking bag. Pour marinade over brisket, 1 cup each: Liquid smoke, soy sauce 1/3 cup each: celery seeds, black pepper, Worcestershire sauce 1/6 cup each: garlic powder, onion salt Fold up foil and seal, or follow instruction on baking bag. Let stand in fridge overnight. Bake in bag or foil for 5 hours at 300 degrees. Or until tender. I scrape off the fat that is left on brisket, along with extra seasonings. Let set, then slice thin and serve.