Preheat your oven to 350°F (175°C) and grease a 9x5-inch loaf pan.

In a medium bowl, whisk together flour, baking powder, baking soda, salt, and cinnamon.

In a large bowl, mix together vegetable oil, brown sugar, and granulated sugar until smooth. Add eggs and vanilla extract, mixing until light and fluffy.

Shred zucchini and squeeze out excess moisture, then fold into the wet mixture.

Gently stir the dry ingredients into the wet mixture until just combined.

Pour the batter into the prepared loaf pan and bake for 50-60 minutes, checking with a toothpick for doneness.

Cool in the pan for 10-15 minutes, then transfer to a wire rack to cool completely.