Transfer the dark chocolate into a bowl and melt it in the oven, microwave or on a double boiler.
Meanwhile mix the egg white with the cream of tartar and the sugar. Blend it till smooth and then while blending add 10 grams of the xanthan gum sugar blend we made before.
Place the bowl on a double boiler (that’s a pan with simmering water) and while mixing heat it up till the temperature is 54 °C (129 °F).
Then place the bowl on a stand mixer and start beating it. Do be careful! The egg whites overwhip very fast. It’s better to under whip, then overwhip.
Now add a quarter of the meringue to the melted chocolate and fold everything together. Once it’s an even mixture add the remaining meringue and fold this in as well. This time be more careful, you want to save as much air as possible.
Then fill the cups till half a centimetre under the rim. Tap the bottom of the cups to level them. Now let them set for 15 to 20 minutes in your fridge.
Once set you can turn them around on a tray and keep them in your fridge. You can keep them up to 48 hours before they need to be baked. We do this later when finishing the dessert.
