Make the base composition by boiling sugar, cocoa powder and water for 5 minutes.
Add the egg yolks one at a time, stirring well with a mixer.
Divide into three parts.
To get the dough, mix 1 part of the base composition with a tablespoon of flour and two tablespoons of breadcrumbs.
Beat egg whites with 3 tablespoons sugar until foamy and add them to the dough composition.
Coat a baking tray with parchment paper and pour the dough composition.
Bake at 200 C = 395 F for about 30 minutes.
Put the cake on a plate.
Alternatively, you can bake the cake in two or three separate smaller baking trays so you won't have to cut it in half once baked.
For the filling, mix the remaining two thirds of the original base composition with butter and mix well.
Add remaining ingredients and mix well.
After you get a smooth filling, place in the fridge and leave it to cool for an hour.
If you made the cake in a single tray, cut it in half.
Put cream between the two cakes.
Make the frosting by melting chocolate in 1 tablespoon still water and mixing with powdered sugar until smooth.
Cover the cake with frosting and let cool until the next day.
Notes
I recommend you pour the dough into 3 separate smaller baking trays to make this recipe even more easy to prepare. Add a layer of sour cherry jam before the filling layer to give a special taste to this cake If you are nuts about nuts don't be afraid to add some crashed nuts to your filling Purchase cake decorating supplies to add sparkle to your cake If your frosting is not quite top notch (or you mess up layering it as I did), decorate with cream, using a fork and a cake syringe Decorate with whipped cream at fancy events