Pulse gingersnap cookies in a food processor until they resemble fine crumbs. Combine cookie crumbs with melted butter and salt in a mixing bowl. Press this mixture into a 9-inch pie plate and refrigerate for at least 30 minutes to set.

In a stand mixer, beat cream cheese and powdered sugar together until smooth. Add pumpkin puree, vanilla, and pumpkin pie spice, mixing until combined.

In a separate bowl, whip heavy cream until stiff peaks form. Gently fold whipped cream into the pumpkin mixture.

Pour the pumpkin mousse into the chilled crust, smooth the top, and cover with plastic wrap. Chill for at least 3 hours.

For topping, whip additional heavy cream with powdered sugar, maple syrup, cinnamon, and vanilla until soft peaks form. Spread atop the mousse.

Slice and serve garnished with extra cinnamon or pecans, enjoying the flavors of fall.