Preheat your oven to 350°F (175°C) and prepare a 9x5-inch loaf pan. Grease it lightly with cooking spray or butter.

In a medium mixing bowl, whisk together the all-purpose flour, cocoa powder, baking soda, baking powder, and salt.

In a larger mixing bowl, beat together the eggs, granulated sugar, and brown sugar until light and fluffy, about 3 minutes. Gradually incorporate the vegetable oil and vanilla extract.

Stir in the sour cream (or Greek yogurt) and grated zucchini into your wet mixture, ensuring the zucchini is well-drained.

Gradually add the dry ingredient mixture into the wet mixture, folding together gently.

Fold in the semi-sweet chocolate chips gently, reserving some for topping later.

Pour the batter into the prepared loaf pan and sprinkle reserved chocolate chips over the top.

Bake for 55-65 minutes until a toothpick inserted comes out with a few moist crumbs.

Allow the bread to cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely.