In a bowl mix the gluten free flour with the cacao powder and the softened butter using your hands until you have a sandy texture.
Add the xanthan gum, the salt and the egg and mix well until you can form a ball.
Fill in contact and refrigerate for 30 minutes.
Preheat your oven to 180°C and roll out the dough on baking paper to form a circle (about a centimetre thick).
Place the circle on a tray with another sheet of baking paper on top and a heavy heat resistant dish to make sure the dough doesn’t rise.
Bake for 20 minutes and set aside to cool down completely.
In a large bowl, mix the cream cheese with the cream and the 20 of sugar and the vanilla sugar.
Melt the chocolate and add it to the cheese. Whisk it in until the mixture is fluffy.
Spread a thick layer of chocolate filling on the cacao base and refrigerate for 2 hours minimum.
Melt the chocolate and mix in the cream.
Beat the egg whites with the salt until firm.
Melt the 50g of sugar with a tablespoon of water until you get a transparent sirup. Don’t let it caramelise.
While beating the eggs, add the sugar sirup and keep on beating until it regains room temperature and forms multiple points.
Put the meringue in an icing pouch and decorate the top of the cheesecake.
Finish by caramelising the meringue with a culinary torch.
Last tip: Keep the cheesecake in the fridge until you serve it. You can make the two first steps a day in advance, but the meringue is best with it is made just before serving so that the sugar doesn’t have time to melt in the fridge with the humidity.