Sponge:

• Melt the chocolate together with the butter over low heat. Stir until it is smooth. When completely homogenized, turn off the heat. Add the vanilla and sugar and stir again. Set the cream aside.
• In another bowl, combine the flour, walnuts, cocoa powder, a pinch of salt, and cinnamon. Whisk gently.
• Separate the eggs. Put the whites in the mixer bowl and the yolks into the chocolate cream.
• Get back to the chocolate cream and stir, then add the dry ingredients, folding in carefully. Next add the cooking cream and milk, which will thin out the mixture.
• Mix the egg whites with a pinch of salt until they become firm. When you get a nice foam, fold them into the chocolate cream with upward movements.
• Preheat the oven to medium heat (180 °C/ 350 °F) and line a 20/30 cm ( 8x12 inch) baking tray with parchment paper. Pour the mixture into the tray and smooth it out. Bake for 25 minutes. Turn off the heat and leave the tray in the oven for another 5 minutes, then remove and transfer to a cooling rack.

Cream:

• Heat the cooking cream and orange juice over low heat until almost boiling, then turn off the heat. Put the gelatin sheet to hydrate in cold water. After 5 minutes add it to the warm cream and mix well. Add the mascarpone, grated orange zest, and powdered sugar. Continue mixing until you get a fine consistency.
• Add the vanilla sugar to the whipping cream and mix until the whipped cream is ready. Incorporate the mascarpone with a spatula, using upward movements. Pour the cream over the cake and refrigerate for 2-3 hours.
• Decoration: Melt the chocolate with the butter and cooking cream over low heat. Pour the glaze over the mascarpone cream and carefully spread it with a wide-edged knife. Decorate with lines of chocolate and ground walnut. Slice it with a knife, running the blade under hot water for a smooth cut.

Enjoy!