Peel and wash the potatoes. Peel kohlrabi. Dice both. Peel and finely dice the onion.
Heat the oil in a pot. Sauté the onion in it while stirring until transparent. Add potatoes and kohlrabi and steam briefly. Deglaze with stock and cream. Simmer covered at low heat for about 15 minutes
In the meantime cut cress from the bed. Cut salmon into strips. Take approx. 4 tablespoons of vegetables out of the soup as garnish. Puree the soup finely with the cutting stick. Season to taste with salt, nutmeg and pepper
Arrange the soup in bowls or deep plates. Add vegetables and salmon. Garnish with cress and pepper