Technical Stages :

• cremer the softened butter along with two thrid of sugar using a whisk.
• Separate the eggs.
• Add the egg yolks to the butter/sugar mixture and continue to mix with the whisk until the preparation thickens.
• Add the sifted flour to avoid lumps.
• Quickly mix using the electric beater.
• Beat the egg whites very firm and stiffen them with the rest of sugar.
• Gently add the slightly meringued firm whites to the dough.
• Divide the dough into 2 even parts.
• Flavor one half with cocoa powder.
• Keep the other one plain.
• Pour the uncoloured dough in a silicone cake mold, cover with chocolate flavoured dough and mix with a fork to form the marbling.
• Bake in hot oven 180°C.
• Bake 30 minutes for mini marbled cakes and a good 50 minutes for a large marbled cake.
• When finished, check that the cake is ready by sticking the blade of a stainless knife in it.
• The cake is baked when the blade comes out dry.
• Unmold on a cooling rack.
• Leave to cool before slicing and eating.