Peel the banana and put it roughly chopped into a bowl. Mash into puree with a fork. Add the yogurt and powdered sugar, mix everything well and set aside.
Peel the kiwis and chop them up on a plate with a fork. Those who prefer it finer can puree the fruit in a mixing bowl.
Pour the dessert into glasses. Layer in alternately first fruit puree, then banana yoghurt, finish with yoghurt.