Preheat oven to 350° F. Line a cupcake pan with 15 cupcake liners. (This will likely need 2 cupcake pans).
In a mixing bowl, whisk together all-purpose flour, granulated sugar, baking powder, salt, and cinnamon.
Add in room temperature egg, milk, oil, and vanilla extract. Whisk until the ingredients are combined. Do not overmix.
Fold in the finely shredded zucchini until well dispersed throughout the batter.
Portion the cupcake batter into the cupcake liners about ¾ full using a large cookie scoop.
Bake for approximately 20 minutes until the cupcakes bounce back when gently touched or an inserted toothpick comes out clean.
Remove from the oven and cool in the pan for 5 minutes. Transfer the cupcakes to a wire cooling rack to cool to room temperature.