01 - Set oven to 325°F (163°C). Line a 9x9-inch baking pan with parchment paper, ensuring an overhang for easy removal.
02 - In a medium bowl, combine graham cracker crumbs, granulated sugar, and melted butter. Press this mixture firmly and evenly into the bottom of the prepared pan.
03 - Bake the crust for 8 minutes, then remove from the oven and allow it to cool slightly.
04 - In a large bowl, beat the softened cream cheese and granulated sugar until smooth and creamy. Incorporate the eggs one at a time, mixing well after each addition. Blend in the vanilla extract, sour cream, and all-purpose flour until just combined.
05 - Pour approximately 1 1/2 cups of the cheesecake batter over the cooled crust and spread it evenly.
06 - To the remaining cheesecake batter, add the canned pumpkin puree, ground cinnamon, ground ginger, ground nutmeg, ground cloves, and salt. Mix thoroughly until well incorporated.
07 - Carefully spoon the pumpkin-infused mixture over the plain cheesecake layer and smooth the surface evenly.
08 - Bake for 35–37 minutes, or until the center is just set and exhibits a slight jiggle.
09 - Remove the pan from the oven and allow the bars to cool completely at room temperature. Subsequently, refrigerate for a minimum of 3 hours, or until thoroughly chilled.
10 - Utilize the parchment paper overhang to lift the bars from the pan. Cut into individual squares and serve chilled.