Preheat your oven to 350 degrees F. Line two baking sheets with parchment paper and set them aside.

Grate the zucchini on the fine side of a box grater. Pile it onto a clean kitchen towel, wrap it up tight, and squeeze out as much liquid as you can over the sink. You want the zucchini to feel almost dry to the touch. Set it aside.

In a large bowl, beat the softened butter with both sugars until light and fluffy, about 2 minutes with a hand mixer or a good minute of vigorous stirring by hand. Add the egg and vanilla and mix until combined.

Scatter the flour, baking soda, baking powder, salt, and cinnamon over the butter mixture. Stir until just combined and no dry streaks remain. Do not overmix.

Fold in the squeezed zucchini and the chocolate chips until evenly distributed throughout the dough.

Scoop rounded tablespoons of dough onto the prepared baking sheets, spacing them about 2 inches apart. The dough will be soft but should hold its shape.

Bake for 11 to 13 minutes, until the edges are set and just barely golden. The centers will look slightly underdone, and that is fine. They firm up as they cool. Do not overbake or they will lose that soft, moist texture.

Let the cookies sit on the baking sheet for 5 minutes before transferring to a wire rack to cool completely. They are delicate right out of the oven so give them that resting time.