Step 1: Preheat your oven to 325°F (165°C) and line an 8x8 inch square baking pan with parchment paper.
Step 2: In a medium bowl, mix Graham cracker crumbs, 1/4 cup sugar, and 6 tbsp melted butter until well combined. Press firmly into the bottom of the prepared pan.
Step 3: Bake the crust for 10 minutes, then remove from the oven and set aside to cool slightly.
Step 4: In a large bowl, beat the softened cream cheese and 1/2 cup sugar until smooth. Add vanilla and eggs one at a time, beating just until incorporated.
Step 5: Remove 1 cup of the plain cheesecake batter and set aside. To the remaining batter, stir in the pumpkin puree, cinnamon, ginger, and cloves.
Step 6: Pour the pumpkin batter over the crust. Dollop the reserved plain batter on top and swirl gently with a knife.
Step 7: Bake for 35 minutes. While baking, mix the chopped pecans, brown sugar, and 2 tbsp melted butter in a small bowl.
Step 8: Sprinkle the pecan mixture over the partially baked cheesecake and bake for an additional 15-20 minutes until set.
Step 9: Cool to room temperature, then refrigerate for at least 4 hours before slicing into bars.