Step 1: Preheat your oven to 350°F (175°C). Mix the gingersnap crumbs and melted butter, then press firmly into the bottom of a 9-inch springform pan. Bake for 10 minutes and let cool.
Step 2: Lower the oven temperature to 325°F (160°C). Wrap the outside of the cooled springform pan in three layers of heavy-duty aluminum foil.
Step 3: In a large bowl, beat the softened cream cheese and sugar until smooth and creamy, about 3 minutes.
Step 4: Add the pumpkin puree, sour cream, cardamom, cinnamon, ginger, salt, and vanilla extract. Mix until well combined.
Step 5: Add the eggs one at a time, mixing on low speed just until each egg is incorporated. Do not overmix.
Step 6: Pour the batter over the crust. Place the springform pan into a large roasting pan and pour hot water into the roasting pan until it reaches halfway up the sides of the cheesecake pan.
Step 7: Bake for 60-70 minutes, or until the edges are set but the center still has a slight jiggle.
Step 8: Turn off the oven and crack the door open. Let the cheesecake cool in the oven for 1 hour. Remove and refrigerate for at least 6 hours or overnight before serving.