Preheat your oven to 350°F (175°C).
Grease and flour a 9x5 inch loaf pan.
In a bowl, combine the flour, baking soda, baking powder, salt, cinnamon, and nutmeg.
In another bowl, whisk together the sugar, oil, eggs, and vanilla extract.
Gradually mix the dry ingredients into the wet ingredients until just combined.
Fold in the grated zucchini and walnuts, if using.
Pour the batter into the prepared loaf pan.
Bake for 60 minutes, or until a toothpick inserted in the center comes out clean.
Let the bread cool in the pan for 10 minutes, then transfer to a wire rack.
Slice and enjoy your delicious zucchini bread!