Peel, wash and dice the potatoes. Peel and dice the onion.
Heat the oil in a pan.
Saute the onions until soft and translucent.
Add the potatoes and pour in the wine.
Add the stock, salt and pepper and simmer for 20 minutes, stirring occasionally.
Blitz the soup with a hand blender until smooth.
Fold in the cream and reheat.
Season with lemon juice, salt and pepper.
Whisk before serving to froth up.
Cut the salmon into fine strips and divide between 4 soupplates or cups. Pour over the soup, season with pepper and serve garnished with dill.