1 c. egg whites (7-8)
1/2 c. sifted unsweetened cocoa
3/4 c. boiling water
1 3/4 c. sifted flour
1 3/4 c. sugar
1 1/2 tsp. baking soda
1 tsp. salt
1/2 c. oil
7 egg yolks
2 tsp. vanilla
1/2 tsp. cream of tartar

Let egg whites warm to room temperature, 1 hour. Into cocoa in small bowl stir boiling water until smooth. Let cool 1/2 hour. Preheat oven to 325 degrees. Sift flour with sugar, soda and salt. Make well in center and pour in oil, yolks, vanilla and cocoa. With wooden spoon, beat smooth. Sprinkle cream of tartar over whites. Mix until stiff peaks form. Pour batter over whites. With whisk gently fold. Turn into ungreased 10 inch tube pan and bake 60-65 minutes. Cool over inverted bottle for 1 1/2 hours.

CHOCOLATE MOUSSE CAKE FILLING:

3 c. heavy cream
1 1/2 c. sifted 10X sugar
3/4 c. sifted cocoa
2 tsp. vanilla
1/4 tsp. salt
1 tsp. unflavored gelatin

Combine cream, sugar, cocoa, vanilla and salt; refrigerate 1 hour. With mixer beat until stiff and refrigerate. Sprinkle gelatin over 2 tablespoons cold water to soften. Heat over hot water to dissolve and then cool. Cut 1 inch crosswise slice from top of cake. Cut out a 1 inch cavity in center of cake ring. Measure 2 1/2 cups of filling and stir in gelatin. Use to fill cavity. Replace top. Mix 1/2 cup filling and 1 1/2 cups crumbs to fill center. Frost with filling and refrigerate.