Clean, wash and slice the zucchini. Blanch in boiling salted water for 1-2 minutes. Mix vinegar with salt, pepper and sugar. Whip oil into it. Add hot zucchini slices to the marinade and mix well.
Coarsely crumble the sheep's cheese. Wash the thyme. Pluck the leaves. Spread the zucchini slices on 4 plates. Sprinkle sheep's cheese and thyme on top. Sprinkle with coarse pepper. Serve with Italian white bread.