Preheat oven at 180C (Conventional oven), Line 3 round 20cm (8 inches) pans grease with oil spray or butter and line with baking paper
Sift cocoa powder and flour into a medium-size bowl and leave aside
In a cake mixer with the whisk attachment whisk eggs then slowly add sugar little by little and beat on high speed for 6-7 minutes until pale in colour and double in size Once doubled in size add vanilla whisk for further 10 seconds.Do not skip this steps, there is no leavening agent ( baking powder or baking soda in this cake, the whipped eggs are what is going to give volume to the cake) Fold in the egg mixture to the flour mixture by HAND try not to deflate the eggs
Lastly, add in the melted butterYou might see the mixture deflate slightly, but that's ok, make sure the butter mixture is not hot Pour the mixture equally into the 3 lined pans and bake in the oven for 20-25 mins until cooked and when a skewer inserted into the cake, it comes out clean
Take out the cake, cool for 10 minutes then turn the cake onto a wire rack to cool off completely