Preheat your oven to 180°C (350°F). Grease and line two 9-inch round cake pans with parchment paper.
Melt 150g of dark chocolate and 120g of butter together in a double boiler or microwave until smooth. Allow to cool slightly.
In a large mixing bowl, whisk together sugar, cocoa powder, and a pinch of salt. Mix in the melted chocolate mixture.
Incorporate the eggs one at a time, then add the scraped seeds from the vanilla pod. Fold in the flour gently until just combined.
Divide the batter evenly between the prepared pans and bake for 25-30 minutes or until a toothpick comes out clean.
Let the cakes cool in the pans for 10 minutes before transferring to a wire rack to cool completely.
For the filling, beat together cream cheese and mascarpone until smooth. Whip 100ml of heavy cream and fold it into the cheese mixture, then add 100ml of condensed milk and vanilla sugar.
Soak gelatin sheets in cold water for 5 minutes. Heat a small amount of water, dissolve gelatin, and stir into the cream cheese filling.
Assemble the cake: place one layer on a serving plate, spread half of the filling, then place the second layer on top and spread remaining filling.
For the ganache, heat 250ml of heavy cream until simmering. Remove from heat and mix in dark and milk chocolate until melted and smooth.
Cool the ganache slightly, then pour it over the cake, allowing it to drizzle down the sides.
Refrigerate the cake for at least 2 hours to set the filling. Slice and serve!
