Pumpkin Spice Sheet Cake

Serve with sweetened whipped cream or frost it with a cream cheese frosting.

• Ready In: 1 hr 25 mins
• Serves: 12

Ingredients

• 1⁄2 cup canola oil, plus additional
•  canola oil, for greasing the pan
• 1 1⁄2 cups cake flour
• 1  cup all-purpose flour
• 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 sugar
• 3  large eggs, at room temperature
• 1 1⁄2 cups canned pumpkin puree
• 1  cup buttermilk (regular or low-fat, but not fat-free)

Directions

1. Position oven rack in center of oven; preheat oven to 350°; dab a little canola oil on a paper towel and lightly grease a 13x9 inch baking pan.
2. Whisk both flours, the baking powder, baking soda, cinnamon, ginger, cloves, salt, and nutmeg in a bowl; set aside.
3. Use an electric mixer to beat both sugars and the eggs in a big bowl until very thick, velvety, and almost doubled in volume, about 5 minutes.
4. Beat in the canola oil, then beat in the pumpkin puree until smooth.
5. Scrape down the sides of the bowl and beat in ½ cup buttermilk.
6. Turn off beaters, add half the flour mixture and beat at low speed just until incorporated.
7. Add the remaining ½ cup buttermilk and beat until fairly smooth.
8. Then add the remaining flour mixture and beat for just a few seconds, until the flour has been incorporated.
9. Remove the beaters; give the batter a few turns with a rubber spatula to make sure there is no undissolved flour, then pour and scrape into the prepared pan, smoothing it gently but evenly to the corners.
10. Bake about 40 minutes, until lightly browned and springy to the touch and pick comes out clean.
11. Set pan on a wire rack for at least 20 minutes before cutting; let cool completely if you are going to frost it.
12. Variations: add ½ cup of any of the following with the flour: semisweet chocolate chips, bittersweet chocolate chips, cocoa nibs, chopped raisins, chopped dried cranberries, or chopped dried cherries.