Bake cake as per instructions on box. Leaving cake in pan, prick cake with a large, two-pronged fork at 1/2-inch intervals. Dissolve gelatin in boiling water. Add cold water and spoon over cake. Chill cake in the pan for 4 hours. Dip pan in warm water for 10 seconds; unmold onto a serving plate. Frost. Garnish as desired, and refrigerate.