Grease and flour two 23 cm cake pans. Preheat oven to 350 deg. Separate eggs. Beat egg whites until frothy; then beat in sugar until stiff peaks form. Set aside. Cream butter and brown sugar until fluffy. Beat in yolks one at a time. Sift flour, cocoa, baking soda tog. Add to creamed mixture alternately with coffee and Frangelico; blend well. Fold egg whites into batter. Pour into prepared pans. Bake 30-35 min. or until done. Cool 10 min. Invert on wire racks and remove pans. Cool before frosting. FROSTING: Cream butter with sugar. Add everything else. and beat until smooth.