Cut the white of the cleaned leeks into rings and stew them with the chopped onion in butter until half soft (set aside a few rings for garnish).
Dust the vegetables with flour, pour boiling clear soup over them and add the raw, peeled, diced potatoes. Cook for about 20 minutes until tender, then strain through a sieve and cool in the refrigerator.
Before serving, fold in the whipped cream and sprinkle with the leek rings and finely chopped herbs.
Our tip: As an alternative to fresh herbs, you can also use frozen ones – these are also characterized by a fresh taste!