How to make
The soft bananas are peeled and pureed in the chopper along with the sugar and lemon juice.
Beat the eggs in a bowl, add the mashed banana mixture, oil and the pre-sifted flour with baking powder.
It is not necessary to use a mixer, mix with a wire whisk or a silicone stirrer.
Pour a portion of the mixture into a 8″ (20 cm) diameter cake mold greased with the soft butter.
About 1 cup is set aside and the cocoa is added to it. Stir, until smooth mixture is obtained and it is poured in a zig-zag pattern over the other mixture.
Bake the marble cake in a preheated oven at 340°F (170°C) for approximately 40 minutes (until a toothpick comes out dry).
The finished and slightly cooled sponge cake is turned over into a suitable plate.
Melt the chocolate and decorate the banana sponge cake as desired and then sprinkle it with ground walnuts.
This sponge cake with soft bananas is a great solution if you have a few overripe bananas left in the fruit bowl.