Pour the whipping cream into a large bowl and whip until soft peaks form.  Gradually start adding the sugar and continue to whip until stiff peaks form.  Add the mascarpone, pumpkin and pumpkin pie spice and beat just until smooth.

Take half of the ladyfingers and line the bottom of a 9-inch springform pan with them, breaking them to fit as needed.  Sprinkle 2 tablespoons of the apple cider over the ladyfingers.  Spread half of the pumpkin mixture over the top of the ladyfingers.  Repeat the layers, with the remaining ladyfingers, apple cider and the remaining pumpkin mixture.  Smooth the top of the tiramisu, cover with plastic wrap, and refrigerate for at least 4 hours, but preferably overnight.

To serve, run a knife around the inside edge of the pan.  Release the sides of the springform pan.  Sprinkle the top of the tiramisu with the crushed gingersnaps.