Sauté the onion cubes in hot oil. Deglaze with the broth, add the carrots and potatoes. Let simmer for about 15 minutes. Add the leek 3 minutes before the end of the cooking time and cook at the same time.
Season the soup with salt, pepper, paprika, nutmeg, mustard and honey to taste.
For the balls, finely chop the smoked salmon and salmon fillet. Add egg white and dill, mix and season with salt, pepper and lemon juice. Chill the mixture for 15 minutes.
Shape the salmon mixture into small balls and add to the simmering soup. Let simmer for about 5 minutes. Arrange and serve the soup.