Beat the eggs with the sugar until whitened with a mixer. Add the flour, sifted together with the baking powder and vanillas. Pour the mixture into a cake form 10 1/4″ (26 cm) in diameter that you've laid out with baking paper.
Bake the cake layer in a preheated 356°F (180 °C) oven with the fan on for about 25 min. or until your toothpick comes out dry when you poke it. Invert the cake layer onto a cake plate.
Preparing the syrup:
Put 1 cup of water with 4 tbsp sugar to boil in a small container on the stove and stir until the latter is fully melted. Add 1 tbsp cocoa and leave it to bubble, then remove from the heat. Pour this syrup over the cooled layer. If you'd like it to be even juicier, you can add a little more water.
Preparing the glaze:
Now pour the melted chocolate over the layer. Decorate as desired. I used chocolate walnuts, chocolate chips and small pieces of a chocolate block.