Prep the pan and oven: Preheat the oven to 350°F (175°C). Line the bottom of a 9-inch springform pan with parchment and lightly grease the sides.
Make the crust: Pulse 30 Oreos in a food processor until fine crumbs form. Stir in melted butter, sugar (if using), and a pinch of salt.
Press the mixture firmly into the bottom and 1–2 inches up the sides of the pan. Use the bottom of a glass to compact it.
Par-bake the crust: Bake for 8–10 minutes, then let it cool while you make the filling. Lower the oven to 325°F (165°C).
Beat the cream cheese and sugar: In a large bowl, beat softened cream cheese with sugar on medium speed until very smooth, about 2 minutes.
Scrape the bowl well to avoid lumps.
Add eggs: Beat in the eggs one at a time on low speed, just until combined. Don’t overmix—you’re trying to avoid extra air.
Flavor the batter: Add pumpkin purée, sour cream, vanilla, spices, and salt. Mix on low until smooth and uniform.
Scrape the bowl again.
Fold in Oreos: Gently fold in the chopped Oreos with a spatula. Aim for even distribution without crushing them completely.
Fill and bake: Pour the batter into the crust and smooth the top. Bake at 325°F for 55–70 minutes, until the edges are set and the center has a slight wobble.
If the top is browning too fast, tent loosely with foil.
Cool gradually: Turn off the oven, crack the door open, and let the cheesecake sit inside for 45–60 minutes. This helps prevent cracks.
Chill: Remove, run a thin knife around the edge, and cool to room temp. Cover and chill at least 6 hours, preferably overnight.
Finish and serve: Remove the ring, transfer to a serving plate, and top with whipped cream and crushed Oreos.
Slice with a hot, clean knife for neat pieces.