Place a rack in the center of your oven and preheat the oven 350F. Line a 8x8-inch metal baking pan with parchment paper, allowing some to hang over two sides. Set aside. Place the shredded zucchini between two paper towels and press out as much water as possible. You can also place it over a sieve and press a paper towel on the top to dry it. Set aside. In a large bowl, mash the banana, then briskly whisk in the eggs, maple syrup, coconut oil, and vanilla. Sprinkle in the coconut flour, cinnamon, baking soda, nutmeg, and salt, then stir until evenly combined. The batter will be very thick. Stir in the shredded, dried zucchini, then fold in 2/3 of the chocolate. Pour the batter into the prepared pan and gently smooth the top. Sprinkle the remaining third of the chocolate on top. Bake for 30 to 35 minutes, until the top is golden and firm and a toothpick inserted in the center comes out clean. Remove from the oven and let cool on a wire rack for 30 minutes, then using the parchment overhang as “handles,†remove the bread from the pan to cool completely.