Preheat oven to 350F.

In a large bowl, stir together the eggs, sugar and vanilla until well blended. Add the zucchini and carrots to the egg mixture and stir well to combine. Add the melted butter to mixture and stir well to combine.

In a separate bowl, stir together flour, baking soda & cinnamon.  Pour flour mixture into wet ingredients and stir until well mixed.  Spray a 12-muffin tin with non-stick cooking spray and evenly distribute muffin mixture.

Bake for 25 to 30 minutes or until a toothpick inserted in the centre of the muffins comes out clean.