Step 1

Preheat oven to 180°C (160°C fan) mark Grease and line a 23 x 33cm (9 x 13in) Swiss roll tin with baking parchment. Using a freestanding mixer or in a large bowl with a handheld electric whisk, beat eggs and caster sugar until extremely thick, about 5min. Beat in vanilla.

Step 2

Sift in flour and cocoa, and gently fold in with a large metal spoon. Scrape into prepared tin and level gently with a palette knife. Bake for 15min until sponge is firm to the touch. Dust top with the extra cocoa and caster sugar, lay a piece of baking parchment on top, then place a wire rack over the top. Invert sponge on to the parchment and rack and gently peel away top lining parchment. While warm, carefully roll up sponge from a long edge, using the parchment to help. Cool on a wire rack (rolled).

Step 3

To make the ganache, whizz chocolate in a food processor until fine (or finely chop by hand), then tip into a heatproof bowl. Heat cream and golden syrup in a small pan over medium heat until almost boiling. Pour over chocolate, leave for 2min, then stir gently until melted. Cover loosely with clingfilm and set aside while you make the filling.

Step 4

Whisk cream until it just holds its shape. Beat in melted cooled white chocolate until stiff. Gently unroll sponge, then spread cream mixture over the top. Mix kirsch and jam and drizzle over the cream, then scatter over chopped cherries. With the help of the parchment, roll the sponge up again. Using a serrated knife, cut a short section diagonally from one end.

Step 5

Transfer to a large platter and place the cut section on one side to look like a stump. Slowly pour or spoon ganache over the sponge, spreading with a palette knife. Chill for at least 20min until set before serving.