Prepare a 9×9 inch square baking pan by creating a parchment paper sling with two strips laid perpendicular, greasing the pan lightly before lining.
Crush the Biscoff cookies into fine crumbs using a food processor or crush in a sealed bag with a rolling pin until no large chunks remain.
Mix melted butter thoroughly into the cookie crumbs until the mixture resembles wet sand.
Press the crust mixture firmly and evenly into the prepared pan, paying special attention to edges and corners, then freeze for 15-20 minutes to set.
In a large bowl, beat softened cream cheese on medium speed until smooth and lump-free, scraping down the bowl as needed.
Add sifted powdered sugar and vanilla extract, beat on low then medium speed until fully combined and smooth.
Mix in 1 cup of creamy Biscoff spread and blend until the filling is uniform pale caramel in color.
In a separate chilled bowl, whip cold heavy cream on medium-high speed until stiff peaks form, being careful not to over-whip.
Gently fold one-third of whipped cream into the Biscoff mixture to lighten, then fold in the remaining whipped cream until no streaks remain.
Pour the cheesecake filling over the chilled crust and spread evenly into corners using an offset spatula.
Microwave remaining Biscoff spread in 15-second intervals, stirring until melted and pourable; pour and spread evenly over the cheesecake filling.
Cover loosely and refrigerate the cheesecake bars for at least 6-8 hours or overnight to fully set.
Use parchment paper overhangs to lift the set cheesecake from the pan and slice into 16 squares with a warm sharp knife.