Chocolate birthday cake
A classic in most traditions, including the Italian one. This is a chocolate sponge cake with a cream layer in the middle, covered by a chocolate ganache. It is easy however it does take a little time, but you'll love the results!
Ingredients for the sponge (Pan di Spagna)
5 eggs (at room temperature)
1 vanilla pod
65 gr cornflower
65 gr cream flour
20 gr raw cocoa powder
150 gr sugar (for a better flavour use cane sugar such as Demerara)
1 pinch of salt
1 shot of rum + 1 tablespoon of sugar
Ingredients for the filling: custard (crema pasticcera)
1 vanilla pod
400 ml whole milk (or soy milk)
100 ml fresh single cream (or soy cream)
45 gr cornflour
140 gr sugar (for a better flavour use cane sugar such as Demerara)
Ingredients for the ganache
400 gr dark chocolate
200 gr heavy cream (or soy cream)
Method for the sponge
First of all it's great if you can do the sponge a day earlier than you need it. Do not cut it , just wait until it's properly cooled down and then cover with cling film. Do not put into the fridge.
Put the eggs and the seeds from inside the vanilla pod into a biggish bowl, and whisk it (using a food processor) until it starts changing colour and it's clearly starting to whip up. Add the sugar a bit at a time, continuing to whip it. It will be ready when you can drip it into a continuous line, which can stay "on top" of the cream, without immediately dissolving with the rest (like writing).
Sift all the powders, then add them slowly to the cream mixing from the bottom to the top to avoid disturbing the whipped state of the cream.
Have your cake tin ready, lined with baking paper. Pour the mixture in the tin and level with a small knife.
Bake on the bottom rack of a pre-heated oven at 160 C for 50 minutes (150 C for a fan oven).
Test it with a stick in the center before taking it out of the oven, if the stick comes out clean the sponge is ready).
Wait ten minutes before taking the cake out of the tin and place it onto a cool wire rack to cool down.
Method for the filling
Take all seeds out of the vanilla pod. Reserve the seeds and put the empty pot in a pot with the milk and the cream. Heat up but don't let it reach the boiling point.
Whisk in a heavy pot (off the hob) the eggs with the vanilla seeds and the sugar until they change colour and look quite creamy. Sift the cornflower and add it to it.
Take the vanilla out of the milk and start adding the milk to the cream one ladlespoon at a time (take care to mix well especially the first spoon or two) until you finish the milk.
Place the pot on the hob and mix slowly on medium heat until the cream will be quite thick (remember you want to be able to spread it nicely).
Have a very big pot ready with cold water and icecubes, and a bowl that can fit inside that pot. Pour the custard into the bowl and stir constantly until it is cool enough to eat. In this way the consistency of the custard will be maintained and no skin will form in the short term.
Assemble the cake
Take your sponge cake and divide it in two using a breadknife. Put 100 ml of water and the teablespoon of sugar into a small pot and let it dissolve completely. Take it off the heat and mix until it arrives to a temperature you could drink it at. Add the glass of rum.
Wet lightly both halves of the sponge (the internal part) with this rum syrup.
Spread the custard on top of the bottom layer and wait a few minutes for it to settle. Cover with the top layer.
Method for the ganache
Break the chocolate in small enough pieces, put int into a bowl and microwave for 1 minute. Pour the cream into another bowl and microwave for 1 minute (watch it, it must not boil).
Pour the heated cream onto the chocolate and wait 2 minutes, then start whisking slowly from the center rotating in one direction only until all chocolate dissolves. Continue whisking until you are sure that it's perfectly amalgamated. It will have a dark rich brown colour.
Drizzle the ganache over the cake and spread it with a knife, trying to drip it and spread it over to cover the borders.
Leave the cake to settle for two hours at room temperature to allow the ganache to harden.