Make the flax egg by whisking together the ground flaxseed and water in a small mixing bowl. Set aside for 5 minutes to thicken.
Add the flour, cocoa powder, coconut sugar, baking soda and salt to a big mixing bowl and whisk until thoroughly combined.
To another mixing bowl, add the shredded zucchini, yogurt and oil. Add the flax egg and mix all together.
Add the wet ingredients into the dry ingredients. Divide up into 3 mini loaf pans (or one big loaf pan or cupcake tins!) Bake for 35 to 40 minutes until a tester comes out dry. Let cool completely. Enjoy!