Preheat the oven to 350°F. Spray an 18 × 13-inch rimmed half-sheet pan with cooking spray. Sprinkle sugar over the pan, then tap out any excess.
In a large bowl, whisk together the granulated sugar, brown sugar, pumpkin purée, eggs, oil, and vanilla until smooth.
1 cup granulated sugar, ¾ cup brown sugar, 1 cup canola oil, 15 ounces pumpkin puree, 4 eggs , 1 tablespoon vanilla extract
In a second bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon, ginger, cloves, and nutmeg.
2 cups all-purpose flour, 2 teaspoons baking powder, 1 teaspoon baking soda, 1 teaspoon salt, 2 teaspoons ground cinnamon, ½ teaspoon ground ginger, ½ teaspoon ground cloves, ½ teaspoon ground nutmeg
Add the dry ingredients to the pumpkin mixture. Whisk just until no dry flour remains, scraping the sides and bottom of the bowl as needed.
Spread the batter evenly in the prepared pan, all the way to the edges.
Bake for about 20 minutes, until the center springs back lightly when touched and a toothpick inserted in the center comes out clean or with a few moist crumbs.
Cool the cake completely in the pan on a wire rack before frosting.