Peel onions. Peel potatoes and celery. Clean leek. Cut vegetables into small pieces and sauté in hot fat. Pour in clear soup and cook for 15 minutes. Add whipped cream and crème fraîche. Let it boil once, season with spices and juice of one lemon and blend with hand blender. Cut the cress into small pieces with scissors and add to the soup with the peppercorns.
Tip: Stock up on high-quality spices – it pays off!