Preheat your oven to 325°F (160°C).
In a mixing bowl, combine the Biscoff cookie crumbs and melted butter. Stir until evenly coated.
Spoon the crumb mixture into the bottom of each cup, pressing down firmly.
In a clean mixing bowl, add cream cheese and mascarpone cheese. Beat until smooth and creamy, about 2-3 minutes.
Add sugar, vanilla, and flour to the mixture. Beat until well combined.
Add the egg and beat on low speed until just combined.
Spoon the filling over the prepared crusts, filling them about ¾ full.
Bake for about 20-25 minutes, or until the edges are set and the center slightly jiggles.
Let cool at room temperature for about 10 minutes, then transfer to a cooling rack.
Cover and refrigerate for at least 2 hours (or overnight) to firm up.
