Preheat oven to 350?F. Pulse graham crackers in a food processor until fine crumbs form.

In a medium bowl, stir together graham cracker crumbs, sugar, cinnamon, and melted butter. Transfer into a 9-inch springform pan and press crumbs into the bottom and sides of the pan. Bake for 8 minutes and cool to room temperature.

Preheat oven to 325?F. In a mixer bowl, beat softened cream cheese and brown sugar on medium speed until light and fluffy, about 5 minutes.

In a separate bowl, whisk together pumpkin puree, eggs, sour cream, flour, pumpkin pie spice, salt, and vanilla extract until well combined. Add this mixture to the cream cheese filling and mix on low speed until well combined.

Pour the filling into the pre-baked and cooled crust, tapping the pan on the counter to release air bubbles. Place a loaf pan half filled with hot water in the oven and bake cheesecake in the center for 50-60 minutes, until edges are set and center has a slight wobble.

Turn off the oven and prop the door open with a wooden spoon for 30 minutes to cool slowly.

Run a knife around the edges of the pan to release tension. Cool on a rack until room temperature, about 2 hours. Wrap in plastic wrap and refrigerate for at least 4 hours or overnight.

Serve chilled with optional toppings.