This recipe is reprinted with permission from Just Desserts, by Charlotte Ree, published by Macmillan (2019).
For the Cake
- 3 large eggs, at room temperature
- 1/ 2 cup plus 2 tablespoons castor sugar
- 1/ 2 cup plus 2 tablespoons all-purpose flour
- 1/ 2 teaspoon baking powder, sifted
- 1/ 4 cup Dutch-process cocoa powder, sifted, plus extra to dust tea towel
- 1 tablespoon powdered sugar, sifted, to dust tea towel
- 1 tablespoon instant coffee granules
- 3 1/ 2 ounces boiling water
- 1 tablespoon Frangelico
- 2 3/ 4 ounces dark chocolate, 70% cocoa, roughly chopped
For the Filling
- 2 cups mascarpone, at room temperature
- 3/ 4 cup plus 1 tablespoon heavy cream, at room temperature
- 3 tablespoons powdered sugar, sifted
- 1 teaspoon vanilla bean paste
For the Topping
- Leftover filling mixture
- 2 tablespoons Dutch-process cocoa powder, sifted
- 3 1/ 2 ounces dark chocolate curls
First, make the filling by placing the mascarpone in the bowl of a stand mixer fitted with the whisk attachment and beating until smooth. Add the cream, icing sugar and vanilla and whisk until creamy and smooth. Place in the fridge, covered in plastic wrap, until required.
Preheat oven to 350ºF. Grease a 13x9x1 inch jelly roll pan with non-stick cooking spray and line with baking paper.
Whisk the eggs and sugar in the bowl of the stand mixer on high until thick and pale (about 4–6 minutes) and the mixture has doubled in size. Sift the flour, baking and cocoa powders once more over the egg mixture. Use a metal spoon to fold the mixture until combined, maintaining as much air as possible. Pour into the prepared tin and gently smooth the surface with the back of a spoon. Bake for 10–12 minutes, or until the sponge springs back slightly when touched.
While the cake is in the oven, lay a clean tea towel on your kitchen bench and dust with the extra cocoa powder and icing sugar. Remove the cake from the oven and turn out the sponge onto the prepared tea towel. Peel the baking paper off gently. Starting at the short edge, tightly roll the cake in the towel and leave to cool completely.
Dissolve the coffee granules in the boiling water, then add the Frangelico and set aside to cool.
Unroll the cooled cake. Using a pastry brush, brush the coffee mixture over the cake until covered and all the coffee has been used. Spread the mascarpone mixture over the sponge, leaving a 1/3-inch border to allow for spreading. Sprinkle with chopped chocolate. Gently roll the cake back into a log shape and place on plastic wrap, wrapping the cake and sealing both ends. Place in the fridge to set, alongside a small bowl of any leftover filling mixture.
To serve, remove the cake from the fridge and spread the remaining filling mixture over the top until smooth. Dust with cocoa powder and decorate with chocolate curls. Store leftovers covered in the fridge for up to 2 days.