Lightly dust the worksurface with icing sugar, then roll out one-eighth of the marzipan until 5 mm(1/4 in) thick. Stick to one end of the cake and trim with scissors. Repeat with the other end.
8.Roll out the remaining marzipan into a long strip,5 mm(1/4 in) thick – it needs to be at least 22 cm(8 1/2in) wide and 35.5 cm (14 in) long. Brush with lemon curd. Place the cake on the marzipan at one of the short ends, then trim the width of the marzipan strip to match the cake. Roll the cake, sticking it to the marzipan as you go. Trim the end to neaten. Serve in slices