For the dough
Mix eggs and sugar until the mass is airy and fluffy.
Sift the flour and baking powder into the bowl. Mix all the ingredients together.
Pour the dough into the cake tin. Bake for 25 minutes at 180 °C.
Take your sponge cake out of the oven and leave it to cool down. Cut sponge cake in 2 layers.
For the cream
Whip sour cream with powdered sugar.
Add mascarpone and condensed milk. Whisk everything together.
Cut banana into slices and add it to the bowl with cream.
Place cake tin in the middle of the plate. Transfer the 1st layer of the cake to the plate. Cover it with tender cream.
Top it with the 2nd layer of the cake. Transfer your dessert to the fridge for 3 hours.
Take it out of the fridge, dust with powdered sugar and serve immediately.