Preheat your oven to 350°F (175°C) and grease a standard loaf pan with olive oil or non-stick spray.

In a large mixing bowl, whisk together the all-purpose flour, cocoa powder, baking soda, kosher salt, and espresso powder until fully combined.

Combine the olive oil and both brown and granulated sugars. Mix until smooth, approximately 2-3 minutes.

Add the eggs one at a time to the sugar-oil mixture, mixing well after each addition until light and fluffy.

Gently fold in the vanilla extract, sour cream, and mashed ripe bananas until just combined.

Gradually fold the dry ingredient mixture into the wet ingredients, mixing until just combined with some flour streaks remaining.

Toss the dark and semi-sweet chocolate chips in a bit of flour before folding them into the batter, reserving some chips for the top.

Pour the batter into the greased loaf pan, smooth the top, and sprinkle reserved chocolate chips and optional banana slices on top.

Bake for 55-65 minutes, checking for doneness with a toothpick.

Allow the bread to cool in the pan for about 20 minutes, then turn out onto a wire rack to cool completely.