Cake:

In a clean bowl, beat egg whites until stiff peaks form, transfer to a mixing bowl.

Beat egg yolk and sugar together, sift flour and cocoa and add to mixture until all ingredients are incorporated. (I tend to get lazy about sifting dry ingredients, but this time you need to do it so you don’t end up with lumps of cocoa in your batter).

Gently fold beaten egg whites into the mixture, until no streaks remain.

Spray with Pam or grease a 10×15 inch baking pan and then line with parchment paper (the spray on the pan helps the parchment paper to adhere to the surface of the pan so it won’t slide around on you).

Pour batter into lined pan.  Bake at 375 degrees for 10 minutes. Let cool for a few minutes.

Sift about 2-3 tablespoons of icing sugar over a clean tea towel and turn baked cake over the icing sugar (parchment side up).

Gently pull off the parchment paper, and let it cool completely.

Icing:

Beat all ingredients well with an electric mixer. The longer you beat it, the fluffier it gets. You can also use all butter rather than a combination of butter and shortening, but the combination gives it a fluffy, soft texture you won’t get if you just use butter.

Filling:

Beat the whipping cream, icing sugar and instant vanilla pudding powder until soft peaks form.   The instant vanilla pudding powder (you must use instant pudding, the cooked pudding powder doesn’t work) helps the whipped cream to hold its shape and not deflate.  It’s something I use almost every time I make whipped cream. You can omit it, and increase the icing sugar to ¼ cup.

Spread whipped cream over the surface of the cake, leaving about ¼ inch border all around.  Roll up, jelly roll style, using the short side.

Spread the icing all over the rolled up cake, putting some on the ends as well.  I put it on the serving plate un-iced, and then lay strips of waxed paper underneath the cake to keep the plate clean while I spread the icing on it.