01 - Preheat oven to 325°F (160°C). Grease and line a 9-inch (23 cm) springform pan.
02 - Pulse ladyfinger biscuits in a food processor to fine crumbs. Combine with melted butter and instant espresso powder, mixing until all crumbs are moistened. Press mixture evenly onto the bottom of the prepared pan. Bake for 10 minutes, then cool completely.
03 - Stir hot espresso, sugar, and coffee liqueur together until the sugar dissolves. Set aside to cool.
04 - With an electric mixer, beat cream cheese, mascarpone cheese, and granulated sugar in a large bowl until smooth and creamy. Add eggs one at a time, beating well after each addition. Mix in brewed espresso, vanilla extract, flour, and a pinch of salt, blending until just combined.
05 - Brush or drizzle half the cooled coffee soak over the baked crust.
06 - Pour the cheesecake filling evenly over the soaked crust. Gently tap the pan on the counter to release air bubbles.
07 - Place the springform pan into a water bath. Bake for 60 minutes, or until the center is just set and slightly wobbly. Turn off the oven, crack the door open, and allow the cheesecake to cool inside for 1 hour.
08 - Remove from the oven and bring to room temperature. Refrigerate uncovered for at least 4 hours, or ideally overnight, to fully chill and set.
09 - Whip heavy cream with powdered sugar and vanilla extract until stiff peaks form.
10 - Run a knife around the edge, release cheesecake from the pan. Optionally brush or drizzle the remaining coffee soak over the top. Spread whipped cream across the top, dust generously with cocoa powder, and garnish with dark chocolate shavings if desired. Slice and serve chilled.