Heat oven to 350°F (175°C). Coat a 9-inch springform pan with nonstick spray and line its base with parchment paper for simple release.

Using a stand mixer fitted with the paddle attachment, beat the cream cheese for 5-6 minutes until silky and free of lumps.

Slowly incorporate the sugar and flour, mixing until thoroughly blended.

Stir in the vanilla extract and cinnamon, mixing only until combined.

Pour in the heavy whipping cream, beginning on low speed and then raising to high; beat for 1 minute. Scrape down the sides and bottom, then continue beating for 30 seconds to 1 minute to guarantee a lump-free batter.

Add the eggs one at a time, ensuring each is fully mixed in before adding the next.

Transfer the batter to the prepared pan, then tap it on the counter 5-6 times to expel air bubbles.

Bake at 350°F (175°C) for 10 minutes. Without opening the oven door, lower the temperature to 200°F (95°C) and bake for another 30-35 minutes until the center wobbles slightly (like Jell-O, not watery).

Switch off the oven, leave the door ajar, and allow the cheesecake to cool gradually for about 15 minutes.

Take it out of the oven, let it reach room temperature, then chill it in the refrigerator overnight.

Preheat the oven to 350°F (175°C). Generously grease a 9-inch cake pan with vegetable shortening and dust it with flour.

In a medium bowl, whisk together the flour, baking powder, cinnamon, ginger, nutmeg, cloves, and allspice.

In a stand mixer with the paddle attachment, cream the butter and brown sugar on high speed until light and airy. Add the vegetable oil, egg, and vanilla, mixing until well combined. Scrape down the sides and bottom.

Add half of the flour mixture and mix until no dry patches remain.

Pour in the milk and mix thoroughly.

Add the remaining flour mixture and mix until no dry spots are visible. Scrape down the sides and bottom, mixing further if necessary.

Pour the batter into the prepared pan and bake for 15-17 minutes, or until a toothpick inserted into the center emerges clean.

Cool to room temperature, then invert onto plastic wrap, wrap tightly, and refrigerate overnight.

In a stand mixer with the paddle attachment, beat the butter on high speed for 1-2 minutes until smooth and creamy.

Reduce the speed to low and add the powdered sugar one cup at a time, fully incorporating after each addition. Mix in the cinnamon until just combined. Scrape down the sides and bottom, then give it a quick mix.

Add the vanilla and heavy whipping cream, then beat on high speed for 1-2 minutes until the frosting reaches a whipped consistency.

Take the cheesecake out of the springform pan and invert it onto a cake stand. Peel off the parchment paper, spread about 3/4 cup of frosting over the top, and smooth it out.

Position the cake layer on top of the cheesecake, and spread another 3/4 cup of buttercream evenly over the cake.

Remove the pumpkin pie from its dish. Trim the crust from the edges so the pie matches the diameter of the cake and cheesecake. (Use scissors to cut slits in the aluminum pan to release the pie shell without breaking it.)

Frost the entire cake with half of the remaining buttercream, ensuring the gaps between layers are filled.

Refrigerate the cake for 20-30 minutes until the buttercream firms up slightly.

Smooth the rest of the buttercream over the cake, and if desired, pipe a decorative border on top. Dust with cinnamon before serving.

Keep any leftovers in an airtight container in the refrigerator for up to three days.