Step 1: Reduce the Cider. Pour 3 cups of fresh apple cider into a saucepan and bring to a gentle boil. Add optional mulling spices if desired. Reduce heat and let simmer for 30-45 minutes until thickened to about 1/3 cup. Cool completely.

Step 2: Preheat the Oven. Preheat your oven to 350°F (175°C) and prepare a 9-inch springform pan by lining the bottom with parchment paper.

Step 3: Make the Crust. Combine cookie crumbs, melted butter, powdered sugar, and a pinch of salt in a bowl until resembling wet sand. Press into the bottom of the prepared pan and bake for 10 minutes until lightly golden.

Step 4: Prepare the Filling. In a stand mixer, beat room-temperature cream cheese until smooth. Gradually add brown sugar and mix well. Incorporate cooled apple cider, sour cream, vanilla extract, and cinnamon until creamy.

Step 5: Incorporate Eggs and Flour. With the mixer on low, add eggs one at a time. Once all are incorporated, sprinkle in flour and mix until just combined.

Step 6: Bake the Cheesecake. Pour filling into the cooled crust, smoothing the top. Bake in a water bath for about 80-90 minutes until edges are set and center is slightly jiggly.

Step 7: Cool Gradually. Turn off the oven, let the cheesecake cool inside with the door cracked for 30 minutes, then sit at room temperature for 15 minutes before chilling in the refrigerator at least 8 hours.