Melt the 200g dark chocolate.

In a bowl, combine the cake crumbs, melted chocolate, rum, jam, and grated marzipan. Mix until it comes together into a thick, moldable paste.

Divide the mixture in two. Roll each half into a sausage about 35cm long and 2cm in diameter - a sheet of cling film or baking paper makes this easier.

Roll the 350g marzipan out thinly, 1-2mm thick, and cut into two strips large enough to wrap around each sausage.

Lay each sausage onto a marzipan strip and roll up to fully encase it, sealing the seam underneath.

Trim the ends neatly, then cut each log into 6cm lengths.

Dip just the two cut ends of each log into the melted chocolate.

Set on baking paper until the chocolate firms up. Chill if needed.