Rinse scallion and cut into rings.
Peel carrot and cut into slices.
Sauté scallion, carrot and onions in 2 tablespoons of butter. Add sugar and tomato paste and cook briefly while stirring. Add tomatoes and pour in the broth. Simmer for about 20 minutes.
Press the soup through a sieve.
Mix 1 tablespoon whipping cream and creme fraiche together and season with salt and pepper.
Cut out shapes (stars or moons) from the bread slices with a cookie cutter and fry until golden brown in a large frying pan in 2 tablespoons butter.
Distribute soup on 4 plates, top each with a few drops of cream and pull in a star pattern. Put croutons on the soup and serve hot.