Preheat the oven to 350F.
In a medium bowl, combine the flour, cocoa powder, salt, and baking soda.
In a separate bowl, whisk together the maple syrup, eggs, oil, milk, and vanilla. Stir into dry ingredients just until moistened.
Fold in zucchini and chocolate morsels. Fill greased or paper-lined muffin cups two-thirds full. Bake for 18-22 minutes or until a toothpick comes out clean.