Preheat the oven to 350°F. Line a muffin tin with paper liners and set aside. Using a food processor (or a plastic bag and a rolling pin), crush the gingersnaps until fine.
Mix the gingersnaps, butter, and sugar. Divide the mixture evenly between the cups of the muffin tin. Bake 8 minutes, then remove from oven and let cool slightly.
While the crust is cooling, beat together the cream cheese and brown sugar until well blended. Add the pumpkin puree, sour cream, egg, vanilla, flour, and pumpkin spice. Mix until combined. Spoon the filling into the muffin cups, filling nearly to the top.
Bake 20-25 minutes, or until the tops of the cheesecakes have puffed up and do not sink in when touched lightly. Remove from oven and let cool. Chill in refrigerator at least one hour.
When ready to serve, top with whipped cream and drizzle with caramel sauce.
Large cheesecake: To make into a full size pumpkin cheesecake, just double this recipe and add an extra egg. Bake in a 9 or 10 inch springform pan at 350°F for 60 minutes. Turn off the oven and open the door slightly and keep cooking the cheesecake an additional 15 to 20 minutes. Remove from oven and allow to cool completely. Then refrigerate for 3 to 4 hours (preferably overnight).