Preheat your oven to 320°F/160°C and line a 15 cm /6 inch diameter round baking pan with baking paper.
In the bowl of your stand mixer, beat the eggs and sugar together for 5 to 8 minutes, until the mixture doubles in volume.
In another bowl, sift together the flour, cocoa, salt, baking powder and baking soda.
Pour the dry ingredients into the egg-sugar mixture while running the mixer at medium speed and until the mixture is homogeneous, then set aside.
In another container, place the cold whole liquid cream and whisk it until stiff, then gently fold it into the first mixture with a spatula.
Pour this mixture into your mould and bake for about 45-55 minutes.
Leave your cake to cool for a few minutes in its mould, then unmould it and let it cool completely on a wire rack.
Wrap your cake in cling film and place it in the fridge for at least 2 hours.
Preparation of the vanilla white chocolate whipped ganache
Chop the white chocolate finely and place it in a large container.
Place the liquid cream in a saucepan over medium heat and bring to a boil
Then pour the hot cream over the chocolate, stir with a wooden spoon or spatula, the chocolate should be completely melted and the ganache should be smooth
Film on contact and place in the fridge overnight.
On the day, whisk the ganache with a whisk.
then add the liquid vanilla and then the mascarpone in 2 times, and continue to mix until you obtain a thick and firm ganache, use your ganache immediately.
Assembly and decoration
Cut your cake into 3 layers of equal size using a sponge cake lyre or a saw knife.
Use a turntable to mount your cake, place a cake base on your turntable, then place a first layer of cake, garnish with a good layer of whipped ganache (you can use a pastry bag to measure the quantity of whipped ganache).
Place a second layer of cake layer on top and repeat the previous step, finish by placing the last layer of cake and apply with a bent spatula a layer of mounted ganache on top of the whole cake, smooth your cake with one.
Decorate the top of your cake, using the remaining whipped ganache in a pastry bag fitted with a large star tip, sprinkle the top of your cake with cocoa and put your layer cake back in the fridge.