Put the chocolate and coffee into a heavy-based ... Using the paper under the cake to help, roll it up firmly from one of the narrow ends. Rest the cake on its seam. Wrap tightly with the ...

Melt the chocolate with 4tbsp cold water in a ... Spread half the icing over the cake up to the edges. Roll up as you would a Swiss roll: starting at the long side opposite you, use the paper ...

The Great British Bake Off‘s Josh Smalley has prepared a science-led chocolate and caramel Swiss roll recipe ... We'll also keep you up to date with New Scientist events and special offers.