Wash the potatoes. Cook in boiling salted water for 15-20 minutes. Then rinse with cold water and peel. In the meantime, wash chicken fillet and dab dry. Fry for 10 minutes in 1 tablespoon of hot oil while turning.
Set aside, keep the roasting set. Clean and wash the tomatoes, zucchini and mushrooms. Halve the tomatoes, cut the zucchini and mushrooms into wafer-thin slices. Drain mozzarella and cut into slices.
Wash the frisée and pluck into bite-sized pieces. Cut the fillet into slices. For the marinade, clean and wash spring onions and cut into thin rings. Briefly heat the existing roasting set. Add spring onions.
Add vinegar and 4 tablespoons of water, bring to the boil briefly. Season with salt, pepper and sugar. Beat the remaining oil into the mixture. Mix marinade with prepared salad ingredients. Cover and leave to stand for approx. 30 minutes.
Season to taste again and serve.