Chocolate Graham Fingers

MELT 1/2 c. butter in saucepan.
ADD:  1/2 c. brown sugar
            2 T. cocoa (or less)
            1 egg, slightly beaten
Stir well. Boil and simmer 1 minute.
ADD:  1 t. vanilla
            3/4 c. broken walnuts
            1/2 lb. roughly broken graham crackers
Press into 8 x 8 greased pan. Chill. Ice with colored frosting. These taste great!