Tiramisu Charlotte

Ingredients

• 2 tbsp unsalted butter, melted and cooled, plus extra butter for greasing
• 4 large eggs
• 1/2 cup superfine sugar
• 3/4 cup all-purpose flour
• Mascarpone mixture
• 4 large eggs, separated
• 3/4 cup superfine sugar
• 9 oz mascarpone
• Coffee syrup
• 2/3 cup strong coffee, preferably espresso
• 4 tbsp Marsala or Madeira, or to taste
• To finish
• Cocoa powder, for dusting
• 7oz ladyfingers
• 3 1/2 oz dark chocolate, in one piece

Directions

1. Preheat the oven to 350 degrees F. Butter an 8in cake pan, line it with parchment paper, and butter the parchment as well. Set a heatproof bowl over a pan of gently simmering water, making sure the bowl isn’t touching the water, and add the eggs and sugar. Whisk the mixture the whole time, just until the sugar is dissolved and it feels barely warm when you touch it.
2. Lift the bowl off the pan and beat the mixture with an electric mixer on high speed for 5 minutes. Turn the mixer down to medium and keep beating for another 3 minutes. At this point, it should be about three times its original volume, and if you lift the beaters, the batter should fall back in a ribbon that takes a moment to disappear.
3. Sift the flour over the batter and fold it in carefully, combining it fully while keeping as much air in the mixture as you can. Scoop out a large spoonful of batter and stir it into the melted butter to loosen the butter up, then gently fold that back into the rest of the batter.
4. Transfer the batter to the prepared pan and smooth the top lightly. Bake for 25 minutes, until the cake is puffed and golden, or until a skewer poked into the center comes out clean. Leave the cake in the pan for 10 minutes, then turn it out onto a wire rack and let it cool completely.
5. For the mascarpone mixture, beat the egg yolks with ½ cup of the superfine sugar until the mixture is pale and creamy. Add the mascarpone and beat until smooth. In a clean, grease-free bowl, whisk the egg whites until soft peaks form, then gradually add the remaining sugar and continue whisking until you have firm peaks. Fold the meringue gently into the mascarpone mixture and set it aside. For the coffee syrup, stir the coffee and Marsala together in a small bowl.
6. To build the cake, cut the cake into three layers with a serrated knife. Place the first layer in the bottom of a 9in springform cake pan. Brush the top with about a third of the coffee syrup, then spread over just under half the mascarpone mixture. Dust that layer with about 1 heaping teaspoon cocoa powder. Do the same thing again with the second cake layer.
7. Push the ladyfingers down around the inside edge of the pan. Add the last cake layer on top and press it down gently, which helps the ladyfingers attach to the cake. Brush the top with the coffee syrup, then add the remaining mascarpone mixture and level it gently. Chill the cake for 4 hours. Just before serving, use a sharp knife or a vegetable peeler to shave the bar of chocolate. Scatter the chocolate shavings over the cake, then take off the springform collar.