Peel the potatoes, carrots and onions, wash the peppers and tomatoes and cut everything into small pieces.
Sweat the onion in the butter in a saucepan until golden, then add the vegetables and spices and fill up with the vegetable stock. Cook everything together for approx. 25 minutes, then puree.
Add the cream cheese and crème fraîche and stir with the hand blender until the soup is nice and creamy. Sprinkle a few more croutons and some marjoram on top if you like.