4 eggs, separated
1/2 tsp. cream of tartar
1/2 c. sugar (for egg whites)
1/2 c. sugar (for egg yolks)
1/4 c. water
1 1/2 tsp. vanilla
3/4 c. flour
5 tbsp. cocoa
1/4 tsp. salt

Beat egg whites until frothy. Add cream of tartar, beating slightly. Add 1/2 cup sugar gradually, beating well after each addition, until rounded peaks are formed. Beat together, until thick and lemon colored, the egg yolks, 1/2 cup of sugar, water, and vanilla. Sift flour, cocoa, and salt together and fold into egg yolk mixture. Fold gently into egg whites. Pour batter into greased and wax paper lined jelly roll pan, spread evenly to edges. Bake at 325 degrees for 30 minutes. Turn immediately onto a towel sprinkled with confectioners sugar. Remove wax paper and, using towel as a guide, roll cake. Set on rack to cool. Unroll and frost.

JELLY ROLL FROSTING:

1/2 c. butter
1/2 c. shortening
1 c. sugar
3 tbsp. flour
2/3 c. milk
1 tsp. vanilla

Cream together butter, shortening, and sugar. Add remaining ingredients and beat for 12 minutes on low speed.