Shred the zucchini using a box grater, then use paper towels to squeeze the extra moisture out of the zucchini. Set it aside until needed. 1 cup shredded zucchini
Preheat the oven to 350 degrees Fahrenheit. Line a couple baking sheets with parchment paper.
Add the butter, brown sugar, and granulated sugar to a large bowl and mix (the bowl of a stand mixer with a paddle attachment is best). Cream them together at medium speed for a couple of minutes. 1 cup unsalted butter, 1 cup brown sugar, 1/2 cup granulated sugar
Add the shredded zucchini, egg, and vanilla extract to the creamed butter and sugars and mix them together until combined. Scrape down the sides and bottom of the bowl as needed. 1 large egg, 2 tsp vanilla extract
Add the flour, cinnamon, baking soda, and salt to the bowl and whisk them into it until combined. 2 cups all purpose flour, 1 tsp ground cinnamon, 1 tsp baking soda
Add in the chocolate chips and oats and mix on low speed until combined and they are mixed evenly into the dough. 3 cups old fashioned oats , 2 cups chocolate chips
Scoop the dough into 2 TBS sized balls, placing them about 2 to 3 inches apart on a parchment paper lined cookie sheet.
Bake the cookies in the preheated oven for 11 to 14 minutes, or until the tops are set and the edges are slightly golden.
Remove from the oven and let the cookies cool on the sheet for 10 minutes, then transfer them to a wire rack to cool.