An introduction to Sweet Potato Cake with Ginger Milk Glaze with Carla Hall, Cookie Monster, and Chef Gonger (Click on this step or "Make It Now" to view introduction.)
Preheat oven to 350°F. Spray a 9x13-inch pan with nonstick cooking spray. Line the pan with parchment paper, extending the paper over the sides. Spray the parchment paper with the canola oil spray to prevent the cake from sticking. Whisk the all-purpose flour to aerate it before measuring it out into a large bowl, then repeat with the whole wheat flour. Measure and add the sugar, sodium-free baking powder, ginger, cinnamon, nutmeg, and salt. Whisk to combine and set aside. In another large bowl, whisk together the sweet potato purée, eggs, vanilla extract, milk, and canola oil until completely combined and smooth.
Using a wooden spoon or rubber spatula, fold the flour mixture into the sweet potato mixture, a cup at a time, until completely combined with no streaks of dry flour. Pour the cake batter into the prepared pan, then gently shake the pan on the counter to smooth the surface. Bake until a toothpick comes out clean when inserted in the center, 30-35 minutes.
Place the milk, ginger, and vanilla extract in a small saucepan over high heat and bring to a boil. Reduce heat to low and simmer gently 15 minutes, then remove from heat and allow to cool completely. Remove the ginger pieces and discard. Whisk the milk and confectioners' sugar together in a medium bowl until completely blended and smooth. If necessary, add more milk to thin to the consistency of maple syrup, or whisk in more confectioners sugar, 1 Tbsp. at a time, to thicken. Whisk again and transfer to a sauce pitcher or small bowl.
Check to see that cake is done. Remove from oven or add time as needed. Once done, set on a wire rack to cool.
Once the pan is completely cool, lift and remove the cake onto a serving platter or cutting board using the sides of the parchment paper. Run a spatula around the edges of the cake and slide the parchment paper out from underneath. Drizzle the Ginger Milk Glaze over the top before serving.