Preheat the oven to 176°C, lightly grease and line a 9"x5" loaf tin with baking parchment leving some parchment overhanging on either side to help lift out the banana bread.
In a bowl, whisk the flours, cocoa powder, salt and baking soda together till combined.
In another bowl, whish the olive oil with the brown sugar and add the eggs one at a time whisking after every addition.
Now whisk the mashed bananas and the vanilla extract into the frothy egg mixture.
Using a spatula, gently fold in the flour mixture till just combined. Fold in the chocolate chips. Do not mix too vigorously or you'll end up pushing all the air out of the batter.
Rest the batter in the pan for 7-10 minutes to allow the flours to absorb the liquid and hydrate. Then bake for 40 -45 mins or till a skewer inserted into the banana bread comes out clean. If the top browns and the interior is still undercooked, tent a foil over the pan till the bread is done.
Lift the bread on to a wire rack and cool before slicing.