- sunflour oil, for greasing
- 6 free-range eggs, separated
- 175g/6oz caster sugar
- 50g/2oz cocoa powder, sifted
- 25g/1oz shelled almonds
- 25g/1oz shelled hazelnuts
- 110g/4oz caster sugar
- 300ml/10½fl oz double cream
- 50g/2oz cocoa powder, sifted
- 75g/3oz dark chocolate, grated
- For the roulade, preheat the oven to 180C/465F/Gas 4.
- Lightly grease a 23cm x 33cm/9in x 13in Swiss roll tin with a little sunflower oil and line with baking parchment.
- Place the egg yolks and sugar into a large bowl and whisk until light and pale.
- Sift the cocoa powder into the egg yolk mixture and whisk until completely combined.
- In a clean bowl, whisk the egg whites until stiff peaks form when the whisk is removed.
- Add half of the whisked egg whites to the cocoa mixture and mix together well, then gently fold in the remaining whisked egg whites until just combined.
- Pour the mixture into the Swiss roll tin, moving the tin so that the mixture spreads evenly into the corners.
- Transfer to the oven to bake for 20 minutes, or until firm to the touch, then remove from the oven. Place a clean, dry tea towel on top of the roulade and on top of this place another tea towel that has been soaked in cold water and well wrung out. Leave in a cool place for an hour.
- For the filling, heat a dry frying pan until hot and add the almonds and hazelnuts and toast until golden-brown all over.
- Remove the nuts from the pan, allow to cool slightly, then roughly chop.
- Add the sugar to the same pan and return to the heat. Cook until the sugar has melted and caramelised to a golden-brown colour.
- Add the chopped nuts to the caramel and swirl to combine and coat the nuts in caramel.
- Pour the caramel and nut mixture into a well-greased, lined baking tray and leave to cool and set. Once set, remove the mixture and break up into small pieces.
- Whisk the cream until soft peaks are formed when the whisk is removed, then fold the caramel nut pieces into the cream.
- To serve, remove the tea towels from the sponge, and turn out onto a piece of baking parchment that has been dusted with sifted cocoa powder.
- Peel the lining paper from the sponge and spread the whipped cream mixture evenly over the top.
- Starting from a long end, roll up the sponge, using the cocoa-dusted paper to help lift the cake as you roll it forward.
- Once rolled up, dust the roulade with more sifted cocoa powder and sprinkle the grated chocolate over the top.