Preheat the oven to 175 degrees top / bottom heat.
Mix the flour, baking powder, vanilla sugar and sugar in a bowl. Heat the oil, vegetable milk and dark chocolate together in a saucepan on the stove until the chocolate has melted. Then put the mixture in the bowl with the flour mixture and stir with a whisk.
Cut the bananas into small pieces and fold them into the mixture with the chopped almonds.
Grease the baking pan and add the mixture.
Bake the cake in the oven for about 30 minutes. Then leave to cool and, if you like, cover with chocolate icing or dust with powdered sugar.