Preheat your oven to 375°F (190°C). Go ahead and line a couple of baking sheets with parchment paper.
In a medium bowl, whisk together the quick oats, flour, cocoa powder, baking soda, salt, and cinnamon.
In a larger bowl, combine the melted butter and packed brown sugar. Beat them together until they're nicely combined and look smooth.
Beat in the egg and the vanilla extract. Mix until they're just incorporated.
Add the bowl of dry ingredients (from step 2) to the wet ingredients (from step 4). Mix gently until everything is just combined. Stop mixing as soon as you don't see any dry flour spots.
Stir in the grated zucchini and 1 cup of the chocolate chips. Fold them in gently until they're mixed throughout the dough.
Using a spoon or a cookie scoop, drop rounded tablespoons of dough onto your prepared baking sheets. Leave a little space between them for spreading.
Press the remaining 1/2 cup of chocolate chips right onto the tops of each cookie dough ball.
Pop the baking sheets into your preheated oven. Bake for 10-12 minutes. The edges should look set and slightly golden, but the centers still look a tiny bit soft.
Once they're out of the oven, let the cookies cool on the baking sheet for just a few minutes. Then, carefully transfer them to a wire rack to cool completely.