Peel the bananas and place in a bowl. Puree with a hand blender and set aside for now.
Mix the flour with the baking powder and the chopped walnuts. In another bowl, beat the sugar, the soft butter, the milk and the vanilla sugar together with the butter vanilla flavor until frothy. Now add the mashed bananas. Carefully fold in the flour and stir well.
Line a loaf pan with baking paper and pour in the batter.
Bake for 60 minutes and then let rest for another 5 minutes. The cake should be gold in color.
The bread can now be cut into slices, brushed with butter and eaten fresh and still warm.