Arrange oven rack to center of oven and preheat oven to 350F (175C) and grease a 9×5 bread pan with baking spray or grease and flour (tap out excess flour). Set aside.

In a large mixing bowl, combine mashed bananas, oil, sugars and sour cream and stir until well-combined.

Add eggs and vanilla extract and stir well.

In a separate, medium-sized bowl whisk together flour, cocoa powder, baking powder, baking soda, and salt until well-combined.

Add flour mixture to banana mixture and stir gently by hand until ingredients are about 50% combined. Add chocolate chips and continue to stir until ingredients are completely combined (don’t over-mix).

Pour batter into prepared bread pan and scatter additional chocolate chips over the surface, if desired.

Transfer to center rack of 350F (175C) oven and bake for 65-75 minutes or until top of cake springs back when touched or a wooden skewer inserted into the center of the bread comes out clean or with a few moist crumbs (no wet batter).

Allow to cool in pan for 10-15 minutes, then carefully (pan will still be hot!) turn out onto a cooling rack to cool completely before slicing and serving. Enjoy!