Clean, wash, drain and cut the leek into rings. Peel, wash and chop the potatoes. Heat the fat in a saucepan, lightly toast the leek and potatoes. Season with salt and pepper.
Pour in white wine and stock, bring to the boil, cover and simmer for 10-15 minutes.
Wash the dill, shake dry and pluck the banner. Cut salmon into strips
Finely mash the leek and potatoes in the broth. Add parmesan cheese and cream and puree again. Season to taste with salt, pepper and sugar
Arrange soup in deep plates. Place 1 teaspoon each of crème fraîche, salmon and dill on top.