Preheat oven to 350°F. Spray a 9x13-inch baking dish with non-stick cooking spray.
To a medium bowl, add granulated sugar, brown sugar, cinnamon, and nutmeg. Stir to combine.
Add the vegetable oil and mix until incorporated. Add vanilla.
Add eggs, one at a time, whisking until combined before adding another egg. Continue until all of the eggs have been incorporated.
To a separate bowl, add the flour, baking soda, baking powder, and salt. Stir until incorporated.
Combine the dry ingredients with the wet. Mix until combined.
Using a rubber spatula, fold in the zucchini.
Pour the batter into the prepared baking pan.
Place in the oven and let it bake for about 60-65 minutes, or until a toothpick comes out clean with a few crumbs, but no wet batter.
Remove from the oven and let cool completely.