01 - Preheat oven to 325°F. Generously grease a 9-inch springform pan and line the base with parchment paper.
02 - Combine crushed graham crackers, melted butter, brown sugar, and cinnamon in a mixing bowl until evenly incorporated. Press mixture firmly into the base of prepared pan. Bake for 10 minutes, then set aside to cool slightly.
03 - In a large mixing bowl, beat cream cheese and sugar using an electric mixer until smooth and creamy, approximately 3 minutes.
04 - Add pumpkin purée, eggs, sour cream, flour, pumpkin pie spice, vanilla extract, and salt. Beat until just combined, scraping down bowl sides as needed to ensure uniform consistency.
05 - Pour filling over cooled crust. Gently tap pan on counter to release trapped air bubbles. Bake for 50 to 60 minutes until edges are set and center maintains slight wobbly texture.
06 - Turn off oven and crack door open. Allow cheesecake to rest inside for 1 hour. Remove from oven and cool completely at room temperature, then refrigerate minimum 4 hours or preferably overnight.
07 - Whip heavy cream, powdered sugar, and vanilla extract until soft peaks form. Spread or pipe decoratively onto well-chilled cheesecake. Dust with ground cinnamon if desired.
08 - Release springform pan ring carefully. Slice with a clean, warm knife for clean edges and serve immediately.