01 - Preheat oven to 325°F. Grease a 9-inch springform pan and line the base with parchment paper.
02 - Mix crushed graham crackers, melted butter, brown sugar, and cinnamon until combined. Press mixture firmly into the pan base. Bake for 10 minutes, then set aside to cool slightly.
03 - Beat cream cheese and sugar in a large mixing bowl until smooth and creamy.
04 - Add pumpkin purée, eggs, sour cream, flour, pumpkin pie spice, vanilla extract, and salt. Beat until just combined, scraping down sides as needed.
05 - Pour filling over cooled crust. Tap pan gently to release air bubbles. Bake for 50-60 minutes until edges are set and center is slightly wobbly.
06 - Turn off oven, crack door open, and let cheesecake cool inside for 1 hour. Remove and cool completely at room temperature.
07 - Refrigerate at least 4 hours or overnight until fully set.
08 - Whip heavy cream, powdered sugar, and vanilla until soft peaks form. Spread or pipe onto chilled cheesecake. Sprinkle with cinnamon to garnish if desired.
09 - Release springform ring, slice into wedges, and serve immediately.