Make the Crust:Place the cookies and a pinch of salt in the work bowl of a food processor and pulse until broken down into fine crumbs - Pulse in the butter a little at a time until fully incorporated and the texture is similar to wet sand
Press down into a 9 inch pie pan and place in freezer while making the filling
Make the Filling:Clean out the work bowl of the food processor and add the cream cheese, eggs, ¾ cup of the sugar, pumpkin purée, vanilla extract, ground nutmeg, and 1 tsp of the cinnamon - Process (scraping down the sides as necessary) until completely incorporated and smooth
Pour into the crust and spread evenly
Bake on the center rack of the oven for 1 hour
Remove from oven and let sit for 20 minutes
Cover with plastic wrap and refrigerate for a minimum 4 hours to completely set
After the cheesecake has completely set, whisk together the remaining ¼ cup sugar and ½ tsp cinnamon in a small bowl until thoroughly combined
Remove plastic wrap from cheesecake and dust top with cinnamon/sugar mixture
Slice, garnish with whipped cream if desired, and serve chilled