Special equipment: a 9-by-5-inch loaf pan
Preheat the oven to 350 degrees F. Spray a 9-by-5-inch loaf pan with nonstick cooking spray and line with parchment paper.
Sift the flour, baking powder, baking soda and salt into a medium bowl. Add the cornmeal to the dry mix, and whisk together.
In a separate bowl, use a cheese grater to shred the zucchini.
In a large bowl, microwave the butter until melted. Whisk in the sugar, eggs and buttermilk (in that order), until evenly mixed. Use a rubber spatula to fold in the zucchini.
Sift the dry ingredients into the wet ingredients. Some larger pieces of cornmeal won't fit through the sifter; add those larger pieces after sifting, and fold into the batter.
Pour the batter in the prepared pan and bake until a bamboo skewer inserted in the center comes out clean, about 30 minutes.
Cool the bread for about 15 minutes, and then turn out of the loaf pan and set on a wire cooling rack to avoid a soggy bottom. Cool the bread completely, then cut and serve.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.