Place one 8 oz package of cream cheese, ⅓ cup of sugar, and the cornstarch in your mixer bowl. With the paddle attachment, whip the mixture on low until creamy, about 3 minutes. Scrape down the sides of the bowl and add in the remaining 3 packages of cream cheese.
Increase the speed to med-high and whip the remaining cream cheese, sugar and vanilla until smooth.
Mix in the eggs, one at a time, making sure they are fully incorporated before adding the next. Add in the heavy cream and mix until JUST combined. Do not overmix at this stage.
Separate your batter evenly between 2 bowls. In one, fold in the pumpkin puree and cinnamon until evenly mixed.
Gently spoon the two mixtures onto your formed and baked crust. Alternate the two batters, not all of one then the other. When all the batter is spooned in, take a butter knife and carefully swirl the mixture, being careful not to touch the bottom of the pan, until it is swirled to your linking.
Bake the cheesecake in your preheated oven for about 1 hour and 10 minutes or until the center barely jiggles when you shake the pan.
Remove from the oven and allow to cool at room temperature for about an hour before placing in your refrigerator to cool the rest of the way. Cool in your refrigerator for at least 4 hours or overnight.
Once cooled, remove from the springform pan and serve as is, or top with whipped cream. Enjoy!