Preheat the oven to 350°F (175°C).

Grease a 9×5 inch loaf pan with butter or nonstick spray.

Grate the zucchini using a box grater and set aside without squeezing the moisture.

In a large mixing bowl whisk together eggs, sugar, vegetable oil, and vanilla extract.

Stir the grated zucchini into the wet ingredients until well combined.

In another bowl mix flour, baking soda, baking powder, salt, and cinnamon.

Gradually add the dry ingredients into the wet mixture and stir until just combined.

Fold in walnuts or chocolate chips if using.

Pour the batter evenly into the prepared loaf pan.

Bake for 50–55 minutes or until a toothpick inserted in the center comes out clean.

Allow the bread to cool in the pan for 10–15 minutes before slicing and serving.