Wash the potatoes and boil them covered with water. Cook potatoes for 20 minutes. Drain potatoes, rinse with cold water, peel and halve. Wash chicken filet, dab dry and cut into cubes.
Heat 2 tablespoons of oil in a frying pan. Fry the meat until brown. Season with salt and pepper. Peel kohlrabi and cut into small sticks. Clean and wash the salad. Clean, wash and finely dice the radishes, except for 2.
Whip the vinegar and 2 tablespoons of oil. Season to taste with salt, pepper and sugar. Fold in radishes. Arrange salad ingredients on plates. Add some vinaigrette. Serve garnished with radishes.
Add the rest of the vinaigrette.