Preheat your oven to 350°F (175°C) and grease a springform pan. In a large mixing bowl, beat the softened cream cheese until smooth, then blend in granulated sugar, flour, vanilla extract, and cinnamon. Pour in heavy whipping cream and eggs, mixing until just combined. Bake this cheesecake layer for 10 minutes at 350°F, then reduce the temperature to 200°F (93°C) for another 30-35 minutes until it's slightly jiggly. Allow it to cool, then refrigerate overnight.

Preheat your oven to 350°F (175°C) and prepare a cake pan with non-stick spray. In a mixing bowl, whisk together the flour, baking powder, and ground spices. In another bowl, cream the softened butter and brown sugar until fluffy, then add vegetable oil and an egg, mixing well. Alternate adding dry ingredients and milk until combined. Pour the batter into the prepared pan and bake for 15-17 minutes. Once done, allow it to cool before wrapping and refrigerating overnight.

In a large mixing bowl, beat the softened unsalted butter until it’s light and fluffy. Gradually add in powdered sugar, mixing on low speed to avoid a sugar cloud. Once combined, mix in vanilla and a few tablespoons of heavy whipping cream until the frosting reaches a spreadable consistency.

Once all layers are adequately chilled, trim each layer to ensure even sizes. Begin with the cheesecake layer on a cake stand, spreading a generous amount of frosting on top. Next, place the spiced cake layer atop the cheesecake, spread more frosting, then carefully position the store-bought pumpkin pie on top. Frost the entire dessert gracefully and chill for 20-30 minutes to set the layers properly.

After chilling, take your Thanksgiving Piecaken from the refrigerator and apply a final layer of frosting, smoothing it out for an even finish. If desired, dust the top with a pinch of cinnamon for a festive touch. Keep the Piecaken chilled until it's time to serve.