Preheat oven to 350°F (175°C).

Grease and flour a loaf pan.

In a blender, pour 1 cup of vegetable oil.

Add 2 cups of finely chopped zucchini to the blender.

Blend the oil and zucchini until smooth.

Add 3 tsp of vanilla to the blender.

Add 3 eggs to the blender.

Blend all ingredients together until well combined.

In a separate bowl, combine 2 cups of sugar, 3 cups of flour, 3 tsp of cinnamon, 1 tsp of salt, and 1 tsp of baking powder.

Add 1 tsp of baking soda to the dry ingredients.

Gradually add the wet ingredients from the blender to the dry ingredients, mixing until just combined.

Fold in 1 cup of chopped walnuts (optional).

Pour the batter into the prepared loaf pan.

Bake for 50-60 minutes, or until a wooden skewer inserted into the center comes out clean.

Let the bread cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.

Slice and serve.