Cook half of the leeks al dente in salted water and then set aside. Take the salmon out of the fridge.
Melt the butter in a medium-sized saucepan and sauté the onion until translucent. Now add the remaining leek and half of the apple. Sauté both, deglaze with the cider and add the stock. Add the bay leaf and simmer for 10 minutes. Add the cream and bring to the boil once. Salt and pepper, add dill - save a few whole twigs for decoration. Now put the soup in a blender or puree it finely with the blender and let it become frothy.
Cut the smoked salmon into strips.
Serving suggestion: Put the soup in a cup, place it on an oblong plate and next to it put a small pile of apples, steamed leeks and the smoked salmon strips in between. If desired, sour cream can also be added. Put a small dill twig in each soup, see picture.