Preheat the oven to
180º C. Grease a cake tin with a little butter and dust with a little dry flour.
Take the bananas in a
mixing bowl and mash them well. Add sugar and yogurt and beat well with an electric beater. Add eggs and refined oil and beat.
Add whole wheat
flour, baking powder and baking soda and continue to beat with the electric beater till all the ingredients mix well.
Pour the batter into the
greased cake tin, keep it in the preheated oven and bake for 25-30 minutes. Take the cake tin out of the oven and allow to cool.
Cut into slices, arrange
them on a serving platter and serve.