Sift cake flour and cocoa powder together.
Whip eggs and sugar until foamy.
Mix the flour and cocoa powder into the batter.
Pour the batter into a baking pan and bake.
Once the chocolate sponge has cooled, slice it.
Whip fresh cream and sugar together.
Spread whipped cream over the chocolate sponge and layer.
Spread whipped cream over the outside and decorate.