Sift the cake flour. Mash the bananas and make a puree.
Whip the egg whites while adding half of the granulated sugar little by little, and make meringue.
Add the remaining granulated sugar into the egg yolks, and whip. Add the vegetable oil, milk, and bananas, then mix. Mix in the cake flour as well.
Add 1/3 of the meringue, and mix well.
Add 1/2 of the remaining meringue, and mix some more.
Transfer the Step 5 mixture into the bowl with the remaining meringue. Mix lightly on the surface, and mix up from the bottom.
Pour the mixture into the mold from a little height.
Shake the mold side to side, and smooth out the surface. Roll a skewer in the mixture to remove air bubbles.
Bake in the oven for 20 minutes at 170°C, then turn down the temperature to 160°C, and bake for another 10 minutes.
Place it up side down on a glass to cool.
When cooled, cover with a plastic bag.
Run a skewer around the inner edge and a knife around the outer edge of the pan to remove the cake.