Brownie:

• Melt the butter and chocolate over a low heat. When the mixture is smooth, add the sugar and cocoa powder and mix well.
• Whisk the room-temperature mascarpone until it becomes creamy then incorporate it into the chocolate cream. Add the eggs one at a time, mixing well after each one. Finally, add the flour, the seeds from half of a vanilla pod and a pinch of salt.
• Mix gently and pour the mixture into the baking tray.
• Preheat the oven to 160 °C (325 °F) and bake the brownie for 45-50 minutes or until a toothpick inserted into the center comes out clear. Leave the brownie to cool in the pan and start on the decor.

The ganache:

• Melt the chocolate with the heavy whipping cream over a low heat. Pour the cream over the cooled brownie. Level it and refrigerate.

The whipped cream:

• Whisk the whipping cream with the vanilla sugar until frothy. Separately, whisk the mascarpone to make it creamy and then gently fold it into the whipped cream using upward movements. Pour the cream into a piping bag and decorate the cake with rosettes.

Slice, serve, and enjoy!