Prepare Apple Cider: Pour apple cider into a medium saucepan and heat it over medium-high heat. Stir occasionally as it simmers, allowing it to reduce until you have about ½ cup of thick, concentrated cider, roughly 10-15 minutes. Once reduced, remove from heat and let it cool.

Preheat Oven: Preheat your oven to 325°F (163°C). Coat the bottom and sides of a 9-inch springform pan with nonstick spray. Optionally, place a circle of parchment paper on the bottom.

Make Crust: Blend graham crackers in a food processor until fine crumbs. Combine with brown sugar and melted unsalted butter in a mixing bowl until resembling wet sand. Press into the bottom of the springform pan and bake for 12 minutes until slightly golden. Set aside to cool.

Chill Filling: In a large bowl, mix brown sugar, all-purpose flour, and ground cinnamon. Stir in the cooled apple cider and melted butter until well combined. Cover and refrigerate for about 30 minutes.

Mix Cream Cheese Filling: Beat cream cheese and granulated sugar on medium speed until fluffy. Add the apple cider mixture, sour cream, and vanilla. Mix until combined, incorporating eggs one at a time, mixing gently.

Assemble Cheesecake: Pour cream cheese filling over the cooled crust. Spread evenly and gently swirl in the chilled apple cider filling for a marbled effect.

Bake: Place the cheesecake in a shallow baking dish filled with hot water. Bake for 70-80 minutes until the edges are set but the center is slightly jiggly. Watch for a light golden top.

Cool and Chill: Once baking is complete, turn off the oven and crack the door. Let cool in the oven for 30 minutes. Remove and cool completely at room temperature. Refrigerate overnight.