- knob butter, for greasing
- 170g/6oz plain chocolate (70% cocoa solids)
- 5 free-range eggs, separated
- 225g/8oz sugar
- 284ml/10fl oz double cream
- Preheat the oven to 180C/350F/Gas 4.
- Prepare a Swiss roll tin by greasing it with butter and then lining it with a piece of greaseproof paper slightly larger than the tin.
- Gently melt the chocolate in a glass bowl set over a saucepan of boiling water.
- Beat the egg yolks into the sugar.
- When the chocolate has cooled and melted a little, pour it into the egg yolk and sugar mixture.
- Beat the egg whites to stiff peaks, before folding into the chocolate mix.
- Pour the mix into the tin and bake in the oven for 15-20 minutes until firm to the touch – you will know the cake is ready when an inserted skewer comes out clean.
- Run a tea towel under cold water and wring out.
- Place the tea towel over the chocolate roulade once it has cooled a little. After ten minutes remove the tea towel, transfer the roulade to the fridge and leave overnight.
- The next day, sieve icing sugar over a sheet of greaseproof paper a little larger than the tin.
- Tip the cake out onto the fresh greaseproof paper and peel off the other piece of greaseproof paper from the top of the roulade.
- Whip the double cream and smooth it all over the roulade.
- Roll up the roulade, using the greaseproof paper to help hold it together. It may crack a little, but this will not affect the quality of the cake.