Pumpkin Spice Sheet Cake

Serve this autumnal cake with creme fraiche, clotted cream. ,li.1⁄2 cup canola oil, plus additional for greasing the pan

11⁄2 cups cake fl our

1 cup all-purpose fl our

1 tablespoon baking powder

2 teaspoons baking soda

2 teaspoons ground cinnamon

1 teaspoon ground ginger

1⁄2 teaspoon ground cloves

1⁄2 teaspoon salt

1⁄4 teaspoon grated nutmeg

1 cup packed dark brown sugar

1 cup granulated sugar

3 large eggs, at room temperature

11⁄2 cups canned pumpkin puree (do not use canned pumpkin pie fi lling)

1 cup regular or low-fat buttermilk (do not use fat-free)

,ul.

Position the rack in the center of the oven and preheat the oven to 350°F. Dab a little canola oil on a paper towel and lightly grease a 13 ×9-inch baking pan.

Whisk both fl ours, the baking powder, baking soda, cinnamon, ginger, cloves, salt, and nutmeg in a medium bowl; set aside.

Use an electric mixer to beat both sugars and the eggs in a large bowl until very thick, velvety, and almost doubled in volume, about 5 minutes.

Beat in the canola oil, then beat in the pumpkin puree until smooth. Scrape down the sides of the bowl and beat in 1⁄2 cup buttermilk.

Turn off the beaters, add half the fl our mixture, and beat at low speed just until moistened. Add the remaining 1⁄2 cup buttermilk and beat until fairly smooth. Then add the remaining fl our mixture and beat for just a few seconds, just until the fl our has been incorporated. Remove the beaters Give the batter a few turns with a rubber spatula to make sure there’s no undissolved fl our, then pour and scrape it into the prepared pan, smoothing it gently but evenly to the corners.

Bake until lightly browned and springy to the touch, until a toothpick or cake tester inserted into the center of the cake comes out clean, about 40 minutes.

To cool: Set the pan on a wire rack for at least 20 minutes before cutting.

To store: Cool completely, then cover with plastic wrap and set aside at room temperature for up to 2 days or freeze for up to 2 weeks (long freezing dulls the fl avor).

Makes one 13 ×9-inch sheet cake