How to make
Brush a cake form with height 3 cm with butter. Mix sugar with water in a saucepan and bring to a boil.
Add the lemon juice and leave until the caramel becomes golden. Pour in the cake form, so as to cover the bottom. Preheat oven to 410°F (210 °C).
Peel the bananas, cut them in half width and then each in three lengths. Arrange them in the caramelized form, pushing them firmly together.
Sprinkle with vanilla sugar. Roll out the pastry and spread over the bananas. Tuck along the sides of the form.
Put to bake in a preheated oven for about 25 minutes. Remove form the oven, wait about 3 minutes and then turn the finished cake on a serving plate.
Serve warm or chilled.
