Step 1: Preheat your oven to 325°F (165°C) and line an 8×8 inch baking pan with parchment paper, leaving an overhang on the sides.
Step 2: In a medium bowl, combine Graham cracker crumbs, 1/4 cup sugar, and melted butter. Press the mixture firmly into the bottom of the prepared pan.
Step 3: Bake the crust for 10 minutes, then remove from the oven and let it cool completely while you prepare the filling for the haunted pumpkin cheesecake bars.
Step 4: In a large bowl, beat the softened cream cheese and 1/2 cup sugar until smooth and creamy. Add the eggs one at a time, beating well after each addition, then stir in the vanilla.
Step 5: Remove 1/2 cup of the plain cheesecake batter and set it aside. To the remaining batter, stir in the pumpkin puree, cinnamon, nutmeg, and ginger until well combined.
Step 6: Pour the pumpkin batter over the cooled crust. Drop spoonfuls of the reserved plain batter onto the pumpkin layer. Use a knife to gently swirl the two batters together to create a haunted, marbled effect.
Step 7: Bake for 40-45 minutes or until the edges are set but the center still has a slight jiggle. Let the haunted pumpkin cheesecake bars cool to room temperature before refrigerating for at least 4 hours.