- Unsalted butter for coating the pan
- 2 1/4 cups all-purpose flour plus more for coating the pan
- 1 1/2 teaspoons baking powder
- 1 teaspoon ground cinnamon
- 3/4 teaspoon baking soda
- 1/2 teaspoon freshly ground nutmeg
- 1/2 teaspoon fine salt
- 3 large eggs at room temperature
- 3/4 cup packed dark brown sugar
- 3/4 cup granulated sugar
- 3/4 cup vegetable oil
- 1 1/2 teaspoons vanilla extract
- 12 ounces zucchini about 2 to 3 medium zucchini, ends trimmed, grated on the large holes of a box grater (about 2 1/2 cups)
- Heat the oven to 350°F and arrange a rack in the middle. Coat a 9-by-5-inch metal loaf pan with butter and flour, tapping out any excess flour; set aside.
- Place the measured flour, baking powder, cinnamon, baking soda, nutmeg, and salt in a medium bowl and whisk to aerate and break up any lumps. Set aside.
- Place the eggs, sugars, oil, and vanilla in a large bowl and whisk until the eggs are broken up and the mixture is thoroughly combined. Using a rubber spatula, fold in the flour mixture until just combined. Fold in the zucchini until evenly mixed.
- Pour the batter into the prepared pan and spread it into an even layer. Bake until a cake tester or toothpick inserted in the center comes out clean, about 1 hour to 1 hour 10 minutes.
- Transfer the pan to a wire rack to cool slightly, about 15 minutes. Run a knife around the perimeter of the pan and turn the bread out onto the rack to cool completely.