Peel and wash the potatoes and cook them in water with 2 tablespoons of soy sauce, drain, drain and cut in halves or quarters. Wash, clean and slice the zucchini and eggplant. Heat 2 tablespoons of oil and fry both in it. Wash and clean cherry tomatoes. Dice the mozzarella and mix with the vegetables and potatoes in a bowl.
Peel off the garlic clove, press through and mix with the remaining soy sauce, balsamic vinegar and pepper, beat in the remaining oil. Add sugar to taste. Pour the marinade over the salad and let it steep for about 30 minutes. Season again with pepper and soy sauce before serving.
The salad is ideal for a picnic or a party, it can be prepared the day before.