Preheat oven to 350 degrees. In a mixing bowl whisk together flour, cinnamon, baking soda and salt for 20 seconds, set aside.
In the bowl of an electric stand mixer fitted with the paddle attachment whip together butter, granulated sugar and brown sugar until creamy. Mix in egg and vanilla extract.
Add zucchini and with mixer set on low speed, slowly add in flour mixture. Stir in oats, walnuts and chocolate chips (I reserved 1/3 cup of the chocolate chips to press into the tops of dough balls before baking, just for looks which is totally optional).
Shape dough into balls, 2 Tbsp each, then transfer to a Silpat or parchment paper lined baking sheets, spacing cookies 2-inches apart.
Bake in preheated oven 11 - 14 minutes until edges are lightly golden. Cool on baking sheet 2 minutes then transfer to a wire rack to cool completely. Store in an airtight container.
Recipe Source: adapted with slight changes from Nestle