Ingredients

Step by step

1. For the curd, put all the ingredients in a saucepan with 50ml water. Use a balloon whisk to whisk constantly over a medium-low heat until the mixture thickens and starts to come to the boil (about 15-20 minutes). Remove from the heat, strain into a wide bowl and cover the surface with crumpled baking paper. Leave to cool completely.
2. Meanwhile, for the syrup, put the sugar, orange juice (reserve the zest for the filling) and Aperol in a saucepan. Set over a low heat until the sugar has dissolved, stirring occasionally, then bring to a simmer. Simmer gently for 5 minutes, until lightly syrupy. Remove from the heat and stir in the prosecco. Leave to cool completely.
3. Once you are ready to assemble the tiramisu, make the mascarpone filling: put the egg yolks, sugar, orange zest and a pinch of salt in a large bowl and use an electric hand mixer to whisk together until thick and pale (2-3 minutes). Add the mascarpone in 3 batches, whisking well after each addition, until smooth. In a separate bowl, whip the cream until almost holding soft peaks. Use a balloon whisk to fold the cream into the egg mixture until combined, then fold in the prosecco.
4. Dip half the sponge fingers in the cooled Aperol spritz syrup, turning until they are well coated and softened (about 90 seconds). Arrange a layer of the soaked biscuits in the base of a rectangular dish (about 23cm x 18cm x 6cm). Spoon half the mascarpone mixture on top and smooth it over with the back of a spoon. Dip the remaining sponge fingers in the remaining syrup and then arrange on top of the mascarpone. Spoon over the remaining mascarpone and smooth the surface. Use a ballon whisk to vigorously beat the cooled orange curd until smooth, then spoon on top of the mascarpone layer and smooth with the back of a spoon. Chill the tiramisu for at least 6 hours, ideally overnight, before serving.
   
   *This recipe contains raw eggs.