Preheat oven to 350 degrees. Line a 9-inch loaf pan with parchment and coat with nonstick spray (or grease and flour pan generously).
In a large bowl, add brown sugar, oil, eggs, and vanilla. With an electric hand mixer, or vigorously with a whisk by hand, beat until creamy, about 1 minute. Stir in shredded zucchini.
In a second bowl, stir together flour, baking powder, cinnamon, salt, and baking soda. And the flour mixture to the zucchini mixture and stir until just combined; do not over-mix. Scrape into prepared loaf pan.
Bake until the bread is firm and starts to pull away from the sides of the pan and a toothpick inserted into the middle comes out clean with a few crumbs attached, about 50 to 60 minutes.
Cool in pan for 10 minutes. Remove from pan, place on a rack, and cool completely.
