Preheat oven to 350°F (176°C). Lightly grease and flour an 8-1/2 by 4-1/2 inch pan or line with parchment paper, leaving an overhang for easy removal. Grate zucchini on the small holes of a grater. Measure and set aside.
In a medium bowl, stir together the Greek yogurt, honey, and brown sugar until smooth.
In another small microwave-safe bowl, place 1/3 cup (62g) chocolate chips. Melt the coconut oil and measure the oil after being melted. Pour the melted coconut oil over the chocolate chips and stir. Microwave in bursts of 15 seconds, stirring for 20 seconds between each burst until chocolate is fully melted and smooth. Allow to cool to room temperature, then use a spatula to scrape every bit into the Greek yogurt mixture. Stir to combine. Add the egg and vanilla extract and stir until smooth.
In a separate bowl, stir together the oat flour(see note 1), cocoa powder, baking soda, baking powder, salt, and cornstarch. Add in the flour and the remaining 3/4 cup chocolate chips (118g). Stir the dry ingredients together.
Add the dry to the wet. Mix in the zucchini. Gently stir until just combined. Overmixing will result in dense bread or a sunken center.
Use a spatula to scrape every bit of the mixture into the prepared pan and smooth the top into an even layer. Top with a few more chocolate chips if desired. Bake for 45–55 minutes or until a toothpick when inserted into the center comes out with dry or moist (not wet) crumbs. The bread should also be pulling slightly away from the sides. Be careful to not overbake; it will yield a much drier, less-tasty zucchini bread.
Remove from the oven and let cool for 10 minutes before inverting it onto a cooling rack to finish cooling. Allow to completely cool before cutting into the bread—otherwise, it’s pretty crumbly! Cut with a sharp, serrated knife. Best enjoyed the same day—see “Storage” notes below.
Notes
Note 1: I use regular old-fashioned or quick oats and quickly pulse them in a blender or food processor until they resemble flour. Then, measure and add to the bowl (the measurement should be taken after the oats are blended, not before).Storage: Store bread airtight for 1–2 days at room temp; after 3–4 days, it may mold due to moisture. Freeze leftovers up to 3 months, wrapped individually. Thaw at room temp for an hour and reheat briefly. Try it with peanut butter for a tasty twist!