Stir starch and 2-3 tablespoons passion fruit nectar until smooth. Boil up the remaining nectar and thicken with the mixed starch. Cover with cling film to prevent skin formation. Let cool for about 30 minutes.
Mix yoghurt, sugar and vanillin sugar until smooth. Whip cream until stiff and fold into the yoghurt
Carefully fold the passion fruit pudding into the yoghurt, so that streaks appear. Pour cream into 4 large glasses and decorate with mint