Sweet Potato Zucchini Bread

1 ¾ cups white sugar

¾ cup vegetable oil

3 large eggs

1 teaspoon vanilla extract

2 cups all-purpose flour

2 teaspoons ground cinnamon

1 teaspoon baking soda

¼ teaspoon baking powder

¼ teaspoon salt

1 ½ cups grated zucchini (see Notes)

1 ½ cups grated peeled sweet potato