Work the prawns with a chopping knife or cleaver until a creamy paste is formed. Do not use a meat grinder for this! Put the paste and the minced chicken in a larger bowl. Beat the egg, whisk with the chicken stock and add to the shrimp paste.
Wash the fresh celery, shake dry and pluck and chop the flawless leaves. Use 1 tbsp of it immediately and freeze the remaining leaves. Measure frozen goods and allow to thaw. Cut the flawless stems crosswise into approx. 3 mm wide rolls and freeze in portions.
Put all remaining ingredients for the balls in the bowl and mix until homogeneous. Cover and let the mixture mature for 30 minutes in the refrigerator.
For the soup, cut off approx. 8 small florets each from a small broccoli and a small cauliflower, wash and cut the stalks crosswise into thin slices. Wash the carrot, cut off both ends, peel and slice it into approx. 3 mm thick slices with a corrugated plane.
Put the ingredients for the broth in a 1.5 liter saucepan and bring to a boil. Reduce heat supply. Shape the cold shrimp mixture into balls the size of a table tennis ball and let them slide into the simmering water. When all the balls, which have floated and risen for about 5 minutes, season the soup with salt and pepper. Add the insert and simmer for 4 minutes.
Spread over the soup bowls, serve warm and enjoy.