Trim the stalk of the zucchetti. Halve the fruit lengthwise without peeling, then cut into strips and these into small cubes. Remove the peel from the onion and garlic and chop finely. Sauté in butter until light yellow. Add zucchetti and steam briefly. Extinguish with soup. Add the juice of one lemon.
Make the soup on a low fire with the lid closed until the vegetables are soft. Remove just under half of the diced zucchini with a skimmer and set aside.
Mash the remaining vegetables along with the cooking liquid. Bring the soup to the boil repeatedly. Stir half cream and crème fraîche with a little bit of hot soup and add. Season the soup with salt and freshly ground pepper.
Chop the dill. Cut the smoked salmon into strips. Add dill and zucchini cubes to the soup. Serve the soup in warmed soup plates or cups. Top with the strips of smoked salmon and bring the soup to the table on the spot.
Tip: Zucchini is a type of pumpkin and therefore low in calories, rich in vitamins and easy to digest – just the thing for a light meal!