Wash and peel the potatoes. Cut approx. 5 potatoes into small cubes, cut the rest into thin slices. Heat some oil in a pan and fry the potato cubes until crispy. Place on kitchen paper and save for insert.
Froth the butter in a wide saucepan, sweat the potato slices and the finely diced onion in them. Pour in the vegetable stock, add salt, pepper, marjoram and bay leaf and cook the potatoes until soft for about 15 minutes. Then remove the bay leaf, add the cream and crème fraîche and puree everything with the hand blender. Season with salt, pepper and a touch of nutmeg and sprinkle with the fried potato cubes.