Peel and finely chop the onion. Peel and wash carrots and potatoes. Put one carrot aside. Cut potatoes and carrots into small cubes. Heat the fat in a saucepan. Fry onion in it until transparent.
Add carrot and potato cubes and sauté. Season with salt and sugar and deglaze with champagne. Add vegetable stock through a sieve. Cook for 15 minutes. In the meantime heat up the oil in a small high pot.
Cut the carrot into fine strips with a peeler and deep-fry in hot oil for approx. 30 seconds. Drain on kitchen paper. Puree the soup with a blender. Add lemon juice, cayenne pepper and 120 g cream and bring to the boil again.
Whip 80 g cream. Spread the carrot soup on plates and add a dollop of cream. Draw fine streaks with a stick of shash mud. Sprinkle "Carrot Grass" on top. Garnish with oregano.