Crush the Biscoff biscuits finely and mix with melted butter until evenly combined. Press firmly into the base of a lined springform pan. Chill while preparing the filling to help it set.

Beat cream cheese on low speed until smooth. Add sugar and mix gently until combined. Add eggs one at a time, mixing slowly after each addition. Stir in cream, vanilla, and salt. Avoid overmixing, which can incorporate excess air.

Pour the filling over the chilled base. Wrap the outside of the pan with foil and place it on a baking tray. Bake at a moderate temperature until the edges are set and the center has a slight wobble.

Turn off the oven and crack the door open slightly. Let the cheesecake cool slowly inside for about an hour to reduce the risk of cracks. Then remove and cool completely at room temperature before refrigerating.

Heat sugar gently until it melts and turns amber. Carefully add butter, then cream, stirring continuously. Remove from heat and add sea salt. Cool slightly before pouring.

Once the cheesecake is fully chilled, pour salted caramel over the top. Spread gently and finish with Biscoff drizzle or crumbs if desired.