Peel and finely dice the onion and garlic. Clean and wash the spinach. Put some small spinach leaves aside for garnishing. Heat the fat in a pot. Fry onion, garlic and spinach in it.
Dust with flour and deglaze with broth. Bring to the boil and simmer for five minutes. Roll up salmon slices and cut into small rolls. Puree the spinach in the stock. Stir in 100 grams of cream, bring to the boil again. Season to taste with salt, pepper and nutmeg. Mix crème fraîche with two tablespoons of cream and horseradish until smooth. Pour soup into plates. Add one tablespoon of crème fraîche to each plate and pull through with a wooden skewer.
Stir in 100 grams of cream, bring to the boil again. Season to taste with salt, pepper and nutmeg. Mix crème fraîche with two tablespoons of cream and horseradish until smooth. Pour soup into plates. Add one tablespoon of crème fraîche to each plate and pull through with a wooden skewer. Add salmon rolls to the soup and garnish with the remaining spinach leaves