Crush one package of Biscoff cookies into fine crumbs. Mix with 1/4 cup melted butter and press into the bottom of a 9-inch springform pan. Bake at 350?F (175?C) for 10 minutes, then cool.

Beat cream cheese and sugar until smooth. Add eggs one at a time, mixing well after each addition. Stir in heavy cream, vanilla, and Biscoff spread (if using).

Pour the filling over the cooled crust. Place the pan in a water bath and bake at 325?F (165?C) for about 1 hour or until the center is almost set.

Turn off the oven and leave the door slightly ajar for 1 hour. Remove from the oven and cool completely at room temperature. Refrigerate for at least 4 hours or overnight.

Warm the salted caramel sauce and pour over the chilled cheesecake. Crush the remaining Biscoff cookies and sprinkle over the top.