Preheat your oven to 350°F (175°C).

Grease a loaf pan or line it with parchment paper.

In a large bowl, combine the all purpose flour, cocoa powder, baking soda, kosher salt, and espresso powder. Whisk together until well blended.

In another bowl, whisk together olive oil, brown sugar, granulated sugar, eggs, vanilla extract, sour cream, and mashed bananas until smooth.

Slowly add the wet mixture into the dry mixture while gently folding it together.

Toss both dark and semi-sweet chocolate chips in a tablespoon of flour before folding them into your batter.

Pour your batter into the prepared loaf pan. Arrange thin slices of banana on top along with a sprinkle of granulated sugar.

Bake for about 55 minutes or until a toothpick inserted in the center comes out clean.

Allow your bread to cool in the pan for about ten minutes before transferring it onto a wire rack.