Preheat the oven temperature to 350°F. Grease a 5x9 loaf pan.
Mix flour, baking soda, baking powder, cinnamon, nutmeg, and salt until well combined. Set that bowl aside for a second.
In another bowl, whisk together oil, granulated sugar, brown sugar, eggs, vanilla, and applesauce until combined. Toss in the shredded zucchini and stir.
Combine the wet and dry ingredients (from Steps 2 and 3) and gently stir. Don't get too crazy, though; just enough to mix it up. Optional: throw in some nuts or chocolate chips.
The bread batter should be a bit thick. Pour it into your loaf pan evenly. Pop it in the oven for about 55 to 70 minutes. If it starts getting too brown on top, cover it loosely with foil. When it's done, stick a toothpick in the middle; if it comes out clean, you're good to go.
Take it out and let it cool in the pan for about an hour. After that, cut it immediately if you can't wait to dig in. But ideally, you should move it from the pan to a wire rack to continue chilling for some time.