Preheat oven to 375F. In a bowl, sift flour, cocoa, baking powder and salt. In a mixer bowl gradually add sugar. Beat eggs and continue beating, then add water and vanilla extract. Reduce beater speed and add dry ingredients. Spread batter onto prepared 15 x 10 x 3/4 inch baking sheet, lined with waxed paper. Bake 12 minutes. Lift cake onto a towel dusted with cocoa. Remove wax paper and roll cake with the towel, starting from the 10-inch end. Cool on a rack.
In a bowl combine all ingredients, cover and refrigerate. After one hour, remove from refrigerator and beat with wire whisk until soft peaks form. Unroll the cake and spread half the cocoa cream on it. Roll it up again, and ice it with the rest of the icing. Garnish with slivered almonds, grated coconut and chocolate chips.
Cajun Country -- New Iberia, Louisiana