Preheat the oven to 350 degrees F. Stir the gingersnap crumbs, brown sugar, a pinch of salt, and melted butter until it resembles wet sand.
Press firmly into the bottom and slightly up the sides of a 9-inch springform pan. Bake 10 minutes, then reduce the oven to 300 degrees F.
Make the Filling
Beat the room-temperature cream cheese and granulated sugar until smooth, then mix in the flour, cinnamon, ginger, nutmeg, and cloves.
Add the eggs one at a time, then blend in the pumpkin, sour cream, and vanilla just until combined. Do not overmix.
Bake and Cool
Pour the filling over the crust and bake at 300 degrees F for 55 to 65 minutes, until the edges are set and the center 2 inches still jiggles.
Turn off the oven, prop the door open, and let the cheesecake sit inside for 1 hour. Cool to room temperature, then chill at least 4 hours or overnight before slicing.
Notes
Room temperature everything: Cold cream cheese, eggs, and sour cream cause lumps.
Cool slowly: The oven-off hour is the real crack insurance. Do not rush it.
Chill overnight: A fully chilled cheesecake slices clean and tastes better.