Preheat oven to 350°F (175°C). In a bowl, combine crushed graham crackers, sugar, and melted butter until damp sand consistency. Press into a 9-inch springform pan. Bake for 7 minutes, then cool.

In a large bowl, beat cream cheese until creamy. Gradually add sugar, mixing well to ensure smoothness.

Add vanilla, pumpkin, pumpkin pie spice, and cinnamon to cream cheese mixture. Blend well until smooth and creamy.

In a separate bowl, beat eggs until blended. Slowly incorporate them into the filling, mixing gently to avoid lumps.

Pour filling into cooled crust, smoothing the top. Bake at 325°F (163°C) for 40 minutes, then reduce temperature to 250°F (121°C) for another 45 minutes.

Turn off oven and prop door open. Let cool for 1 hour, then refrigerate for at least 6 hours or overnight.

Remove from springform pan, garnish with whipped cream and cinnamon, and serve.