Mash the ripe bananas or stir them in the food processor, but do not mash them.
Mix the eggs, sugar, vanilla sugar, salt, oil and milk into the bananas. Mix the polenta with the baking powder and stir in. Let it soak for 10 minutes. It is normal for the dough to be very runny, as the polenta doesn`t really absorb the liquid until it is baked. Fold in the raisins.
Grease a large loaf pan and sprinkle with polenta. Pour the batter into the mold and bake in the lower third of the oven for 45-50 minutes. Do the chopsticks test.