Preheat oven to 350°F. Lightly grease one 9x5 loaf pan, or line it with parchment paper, and set it aside.
In a large bowl, add finely grated zucchini with its liquid, brown sugar, oil, eggs, and vanilla extract. Stir until evenly combined.
In a separate bowl, whisk together flour, baking soda, ginger, cinnamon, cloves, and salt until the spices are evenly distributed.
In a third bowl, whisk together molasses and hot water until fully incorporated and smooth.
Add half of the dry ingredients to the zucchini mixture and stir until just incorporated. Add half of the molasses mixture and stir again until just incorporated.
Repeat with the remaining dry ingredients and remaining molasses mixture, stirring gently until no large dry streaks remain. Do not overmix.
Pour the batter into the prepared loaf pan and smooth the top lightly.
Bake for 48 to 55 minutes, or until a toothpick inserted into the center comes out clean or with dry crumbs. For the most accurate doneness check, the center should reach 200°F to 205°F.
Allow the bread to cool completely on the counter before removing it from the pan. Dust with confectioner's sugar before slicing and serving, if desired.
