Cocoa Sponge Cake
Mix the eggs with the sugar.
Beat the mixture in a mixer for 15-20 minutes at medium speed.
Add the sifted flour and bitter cocoa and with a spatula mix together starting from the bottom to the top of the bowl to obtain a homogeneous consistency.
Put the mixture into the cake pan (9 inches) which should be properly greased and lightly floured.
Bake in a preheated oven at 180°C (356°F) for about 40-50 minutes, never open the oven before 35 minutes.
Do the toothpick test to check cooking, insert it in the center and it should come out clean (if not continue to cook).
Let It cool down.
Slice the sponge into 3 layers.
In a saucepan, add the water and sugar.
Let the sugar melt at low heat. It will take just a few minutes.
Remove the saucepan from the stove and add the milk and mix.
Add the cocoa powder, mix thoroughly so as not to create lumps.
Hydrate the gelatin in cold water for 10-15 minutes.
Put the strawberries in a saucepan with the sugar, stir until the syrup is formed, remove from the heat and blend with an immersion blender.
Add a few drops of lemon juice.
Add the hydrated and squeezed gelatin to the puree and mix until it dissolves.
Brush the soaking mixture evenly over top of the cake layers twice, beginning at the outer edge and working inward. Cool to room temperature.
Cover the surface of the bottom layer with 3 tablespoons of strawberry jam, spreading it evenly.
Carefully cover this layer with another layer of soaked sponge cake and spread 3 tablespoons of Nutella evenly on the surface of the latter.
Place the last layer of sponge cake on the layer of Nutella and glaze with the strawberry puree.
Decorate as you like.