For the crust:
For the filling:
1. Make the crust: In a food processor or a Ziploc bag crush the Savoiardi biscuits, cocoa powder and coffee into fine crumbs. Add melted butter and pulse until combined. Press into bottom of 8-inch (20cm) springform pan. Refrigerate while making the filling.
2. Make the filling: In a small bowl stir gelatin powder and water. Let bloom for 10 minutes.
3. Pour hot coffee into large shallow dish, set aside to cool.
4. In a large bowl mascarpone cheese, vanilla extract and powdered sugar until soft and smooth. In a separate bowl whip heavy cream to medium peaks. Gradually fold into the cheesecake mixture
5. Melt the gelatin in the microwave for 15 seconds. Temper the gelatin: Gradually add few tablespoons of the cheesecake mixture into the dissolved gelatin and stir until combined. Pour back to the cheesecake mixture and mix until combined.
6. Pour half of the cheesecake mixture over the crust, then dip each ladyfinger in the cold coffee for 1-2 seconds. Arrange one layer of soaked biscuits over the cheesecake layer. Then, pour the remaining cheesecake mixture and spread evenly.
7. Refrigerate overnight or for at least 6 hours.
8. Just before serving, dust with cocoa powder.