Place all ingredients other than the cocoa and icing sugar into the Thermomix bowl and brew 7 min/80°C/speed 1. Blend 20 sec/speed 8.
Strain into two cups. There is plenty of foam, so this can be a bit of a pain, but persistence is worth it.
While the brew is brewing, cut a circle of stiff paper that is larger than your cups, and then cut a cross pattern from the centre.
When your drinks are poured, sieve them both with cocoa. Lay the stencil over the top and sieve with icing sugar. The sugar melts quickly, so do this part directly before serving. Enjoy!