Prepare all the ingredients.
the egg yolks.
the yolks with 160 g sugar.
Melt the chocolate in a bain-marie with butter.
Mix well when chocolate is melted.
the cocoa on top of the melted chocolate.
Mix.
Place the egg whites in a bowl with a pinch fine salt.
Beat them very firm.
Add the rest of caster sugar and whisk once again for one minute.
Pour the chocolate mixture on the creamed egg yolks.
Mix thoroughly...
...until you obtain a smooth .
Delicately add the whites...
...until you obtain a smooth preparation.
Pour one third of the batter in a pan and place in the fridge.
Pour the rest in a slightly greased cake pan.
Bake in hot oven...
...at 180°C for 25 minutes.
When finished, leave to cool to room temperature then remove from the mold.
Coat the surface of the cake 2 cm high using the rest of the preparation stored in the fridge.
Place in the fridge for 1 hour.
Bake 10 minutes at 220°C.
When finished...
...remove from the oven and leave to rest 10 mn...
...before serving.