This soup was created by the winner of the iSi Espumas Award 2003: Bettina Mittendorfer.
Finely chop the onion and sauté in a pot with butter. Chop and add the beetroot. Deglaze with vegetable stock and boil the vegetables until soft. Finely puree everything in a blender. Add the heavy cream and the flour, briefly heat and bind. A honey-like consistency is optimal. Finally, season with the spices. Pass the mixture through the iSi Funnel & Sieve directly into a 0.5 l iSi Whipper. Screw on 1 iSi Cream Charger and shake vigorously.
Keep the iSi Whipper warm at a constant temperature of max. 75 °C in a bain-marie or water bath. Shake vigorously once more before serving.
CAUTION: Do not place the iSi Thermo Whip or iSi Thermo XPress Whip in the bain-marie or water bath!
Horseradish dumplings can also be added to the soup. Double the ingredients for a 1 l iSi Whipper. Screw on 2 iSi Cream Chargers, one after the other. Shake vigorously after attaching each Charger. Halve the ingredients if using a 0.25 l iSi Whipper.
Recipe by Bettina Mittendorfer, iSi Espumas Award 2003 (Austria)