Stir together 1 Tablespoon canola oil and 1 Tablespoon all-purpose flour in a small bowl. Brush this mixture all over the inside of a 12-cup bundt pan, being careful not to let it pool in the bottom. Set the pan aside.
Pumpkin Spice Bundt Cake
Move an oven rack to the middle position and heat the oven to 350°F.
In a medium bowl, whisk together 2 ½ cups all-purpose flour, ¼ cup cornstarch, 1 ½ teaspoons baking powder, 1 teaspoon cinnamon, ½ teaspoon baking soda, ½ teaspoon table salt, and ¼ teaspoon freshly grated nutmeg. Set this aside.
In a medium bowl or large measuring cup, stir together 1 ½ cups pumpkin puree, ¼ cup canola oil, and 1 ½ Tablespoons grated fresh ginger. Set aside.
Add ½ cup softened unsalted butter to the bowl of a stand mixer (or to a large bowl). Mix on medium-high speed until fluffy. Scrape down the sides of the bowl with a spatula and add 1 ½ cups granulated sugar to the bowl. Mix on medium-high speed until the mixture is well-mixed, about 2 minutes.
Scrape down the sides of the bowl and add one of the large eggs. Turn the mixer on to high speed and mix until the mixture is fluffy. Repeat this process again with the second large egg.
Scrape down the sides of the bowl and add half of the flour mixture. Turn the mixer on low speed, and mix until the flour is mostly mixed in, then slowly increase the speed to medium until the mixture is fully mixed. Scrape down the sides of the bowl and add half of the pumpkin mixture. Mix on medium-high speed until fully mixed. Repeat this procedure with the remaining halves of the flour and pumpkin mixtures.
Pour the mixture into the prepared bundt pan, and spread it evenly into the pan. Bake for 45-55 minutes until a toothpick inserted into the center of the cake comes out with a few crumbs clinging to it.
Place the cake on a wire rack to cool for at least 20 minutes before attempting to remove the cake from the pan. To remove the cake from the pan, place a large plate or platter over the pan, and quickly and carefully flip both the plate and the pan so that the plate is on the bottom. The cake should come out easily. Allow the cake to cool completely before adding an optional glaze.