1. Marinate the prawns before you start to make the soup: pat them dry with kitchen paper and place them in a mixing bowl. Add the oil, the ? tsp Ras-el-Hanout, smoked paprika, salt and pepper. Stir to coat the prawns then set aside.

2. Weigh the butter, celeriac and the ? tsp Ras el Hanout into the TM bowl. Chop at Speed 6 for a few seconds then cook 8 minutes/100?C/Speed 2.

3. Cook again for a further 2 minutes/Varoma Temperature/Speed 2.

4. Add the stock and cook 12 minutes/100?C/Speed 2. While the soup is cooking, place the marinated tiger prawns in the Varoma tray. Place the covered Varoma on top of the TM lid for the last 6 minutes of the cooking time, turning them after 3 minutes.

5. Remove the Varoma, keep the prawns warm. Add the double cream to the soup and blend 1 minute/Speed 9. Taste and add salt and pepper if desired.

6. Pour the soup in to the cream whipper. Secure the lid and charge with two N?O gas pellets, shake vigorously and squirt the foamy soup into 12 warm shot glasses (for amuse bouches) or 6 warm small cups (for starters). Skewer the prawns onto wooden toothpicks and serve the soup with the skewered prawns. Garnish with sprigs of cress.

Janie's Tip:

Tip: If you use a Gourmet Whip cream whipper, the soup can be kept warm in a bain marie with boiling hot water or in a water bath for up to one hour. Gourmet Whips and chargers available from UK Thermomix 01344 622 344.