Heat oven to 350° F (177° C). Lightly grease a 5-inch baking dish (or use a dish of similar size) with cooking spray or butter.
Mix together the egg, oil, sugars, applesauce, and vanilla in a medium-sized bowl. Stir in the zucchini.
Add the flour, cocoa powder, baking powder, baking soda, and salt. Stir until no flour remains, being careful not to overmix.
Stir in the chocolate chips.
Pour the batter into the baking dish and bake for 30 minutes. A toothpick inserted in the center should come out clean.
Cool in the pan for 10 minutes. Remove from the pan and transfer to a wire cooling rack to cool completely.
Slice and top with powdered sugar, if using.
Notes
Before you start baking, make sure to read the entire recipe, including the Ingredient Notes section, and examine the process photos. This detailed guide will help you understand how the recipe unfolds, ensuring your chocolate zucchini bread turns out perfect every time. All the information you need is found within the body of this recipe post, so don’t miss a thing!
Grating Zucchini: A box grater (hand grater), mini food processor, or a high-powered blender like Vitamix will do the job effectively.
Zucchini Moisture: Resist the urge to squeeze the zucchini. Retaining its natural moisture ensures a succulent loaf.
Flour Measurement: Adhere to the spoon and level technique as detailed in the recipe post for precise measurements.
Mixing Method: Gently combine the ingredients. Overzealous mixing can lead to a loaf that's dry and less tender.