Preheat the oven to 375°F (190°C). Line a muffin pan with 10 liners and set aside.
In a large mixing bowl, whisk together the flour, ground cinnamon, baking powder, baking soda, nutmeg, and salt until well combined. Set aside.
In a separate large mixing bowl whisk together the oil, brown sugar, eggs, and vanilla extract until fully combined. Stir in the shredded zucchini.
Add the dry ingredients to the wet ingredients and mix together until just combined.
Evenly divide the batter between all 10 liners in the prepared muffin pan, filling each one almost to the top.
Bake for 18 to 23 minutes or until a toothpick inserted into the center comes out clean.
Remove from the oven and carefully remove the muffins from the pan, then transfer them to a wire rack to cool completely.