Coat brisket well with tenderizer. Wrap with 2 layers of heavy duty foil. Refrigerate overnight. Place in Dutch oven, cover and cook 225 to 250 for 6 to 7 hours. You can cook it faster but it is juicier cooked slow. Remove from foil and place on warm serving plate. Using the juice, flour, salt and pepper, make a thin gravy. Pour gravy over brisket before serving.