Preheat the oven to 350˚F (175˚C). Grease and line a loaf pan with parchment paper so that there is an overhang on both sides (*as shown in the pics above).
Sift the flour, cornstarch, cocoa, baking powder, baking soda, and salt into a mixing bowl and whisk together.
To a measuring jar add the non-dairy milk, oil, sugar, vanilla extract, apple cider vinegar, coffee powder and mashed banana (or another egg substitute *see recipe notes). Mix to combine.
Pour this mixture into the flour mixture and stir until just combined. Then fold in shredded zucchini (make sure it is slightly squeezed) and chocolate chips (or chopped chocolate or melted chocolate *see text above). The batter should be thick but still pourable as shown in the step-by-step pics. If it’s too thick add a tiny bit more non-dairy milk.
Fill the batter into your prepared pan. Optionally, top with more chocolate chips. Bake for about 50-60 minutes, or until a toothpick inserted in the middle comes out mostly clean with some melted chocolate chips attached.
Let cool in the pan completely. Then using the parchment paper to lift out the loaf carefully.
Slice and enjoy with caramel sauce if you like!