Crunchy Chocolate Log
Break the chocolate into small pieces and place in a large heatproof bowl with the butter. Stand over a bowl of barely simmering water. Allow to melt then remove from the water and cool for 10 minutes.
Stir the almonds, citrus peel, crushed biscuits, chopped marzipan and almond extract into the chocolate and mix well. Leave in a cool place for about 30 minutes to firm up, but not set completely.
Turn the firm chocolate mixture on a large sheet of baking parchment and form into a log shape about 25cm (10in) long, with tapering ends. Wrap well in the paper and chill for at least 4 hours until solid.
Mix the ground almonds and icing sugar together and sieve evenly over a sheet of baking parchment to cover and area the same length as the 'log'. Unwrap the 'log' and roll evenly in the sweet almond mixture to lightly coat - the mixture should cling to the 'log'.
Leave to stand in a cool place for 1 hour before slicing with a large knife to serve.