01 - Preheat oven to 350°F. Grease and flour a 9x5-inch loaf pan.
02 - Whisk together flour, baking soda, baking powder, salt, cinnamon, and nutmeg in a medium bowl until evenly blended.
03 - Beat eggs, vegetable oil, granulated sugar, brown sugar, and vanilla extract in a large bowl until well combined and smooth.
04 - Stir grated zucchini into the wet mixture until evenly distributed throughout.
05 - Add dry ingredients to wet ingredients. Fold gently until just incorporated, being careful not to overmix.
06 - Fold in chopped walnuts or pecans if desired.
07 - Pour batter into prepared loaf pan and smooth top. Bake for 50 to 60 minutes until toothpick inserted into center comes out clean.
08 - Let bread cool in pan for 10 minutes, then transfer to wire rack to cool completely before slicing.