Preheat oven to 325 F. Spray a 9x5-inch pan with cooking spray.
Separate the egg whites from the egg yolks. Place the egg whites in the bowl of a stand mixer. Beat the egg whites until soft peaks form. Transfer the egg whites to another bowl.
Place the egg yolks, vegetable oil, vanilla, and sugar in the bowl of the stand mixer. Beat on low until combined.
In a large bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon, ginger, and cloves.
Use a spatula to fold the flour mixture into the oil mixture. Mix just until combined — the mixture will be crumbly. Add the grated zucchini and pecans, and mix just until combined. The mixture will still be crumbly.
Use a spatula to gently fold in the egg whites until no white streaks remain. At this point, a smooth batter will form.
Transfer the mixture to the prepared pan, and bake for 65-80 minutes, or until a toothpick inserted into the center comes out clean.
Let cool for 10 minutes before removing from the pan. Slice and enjoy.