- Prepare the Pan & Crust: Preheat oven to 300°F. 
- Line a 9×13-inch baking dish with parchment paper or foil, leaving an overhang on two sides for easy lifting later. Tip: Even if you spray with nonstick spray, the bars can stick—so lining is highly recommended. 
- In a medium bowl, combine 1 ⅔ cups graham cracker crumbs (about 13 whole graham crackers, finely crushed)with ¼ cup melted unsalted butter and 2 tablespoons granulated sugar. Stir until evenly combined. 
- Press the mixture firmly into the bottom of the prepared pan to form an even crust. Set aside. 
- Make the Cheesecake Filling: In a large mixing bowl (or stand mixer with paddle attachment), beat 4 packages (8 ounces each) of softened cream cheese with 1 ½ cups granulated sugar on low speed until smooth and fluffy. 
- Add 4 large eggs, one at a time, mixing just until combined after each addition. Do not overmix. 
- Mix in 1 cup canned pumpkin puree (not pumpkin pie filling) and 2 teaspoons pumpkin pie spice until smooth. 
- Assemble & Bake: Pour the pumpkin cheesecake filling over the crust and spread it into an even layer. 
- Bake for 50–55 minutes, or until the edges are set and the center is slightly jiggly. 
- Turn off the oven, crack the oven door open, and let the cheesecake bars cool slowly for 60–90 minutes. This helps prevent cracks from forming. 
- Chill & Serve: Cover lightly and refrigerate for at least 3 hours (overnight is best) to fully set. 
- Use the parchment/foil overhang to lift the cheesecake from the pan before cutting into squares. 
- Garnish with whipped cream and a sprinkle of pumpkin pie spice before serving.