1. Preheat oven to 350°F (175°C) and grease an 8×4-inch loaf pan; line with parchment paper.

2. Wash and trim zucchini, grate finely, then squeeze out excess moisture using a clean towel.

3. In a medium bowl, whisk together whole wheat flour, all-purpose flour, cocoa powder, baking soda, baking powder, and salt.

4. In a large bowl, beat eggs, then whisk in maple syrup (or honey), oil, and vanilla extract until smooth.

5. Fold grated zucchini into the wet mixture.

6. Gradually add dry ingredients to wet ingredients, folding gently to avoid overmixing.

7. Stir in dark chocolate chips until evenly distributed.

8. Pour batter into prepared loaf pan and smooth the top.

9. Bake for 50–60 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.

10. Let loaf cool in pan for 10 minutes, then transfer to a cooling rack and cool completely before slicing.