Crush the biscuits into fine crumbs using a food processor or rolling pin. In a bowl, mix the crumbs with melted butter until it resembles wet sand. Press firmly into the bottom of a 20–22 cm springform pan and chill in the fridge for 15–20 minutes.
Step 2: Prepare the Cream Layer
In a chilled mixing bowl, whip the heavy cream with powdered sugar and vanilla until soft peaks form.
Tip: Don’t over-whip. The cream should be thick enough to hold its shape but still smooth. If it turns grainy, it’s over-whipped.
Step 3: Assemble the Middle Layer
Spread the whipped cream evenly over the chilled biscuit base. Smooth the top with a spatula, then return to the fridge while preparing the ganache.
Step 4: Make the Ganache
Heat the heavy cream in a small saucepan until it begins to simmer (do not boil). Pour over the chopped dark chocolate and let sit for 30 seconds. Stir gently until smooth and glossy. Add butter if you want an extra shiny finish.
Step 5: Pour Over the Cream
Let the ganache cool for 5 minutes so it’s not too hot, then pour over the cream layer. Tilt the pan to spread it evenly to the edges.
Step 6: Chill and Serve
Refrigerate the cake for at least 2 hours. Before serving, run a thin knife around the pan’s edge, release the springform, and use a hot, clean knife to cut neat slices.
