melt 1 full size block of dark cooking chocolate over water (a double boiler for those chefs out there).
While it cools finely chop 8 after dinner mints, the stick ones are best but the other ones are fine.
Whip 600mls of thickened cream to firm peaks.
Fold together the melted chocolate, the cream and mint until combined. Refrigerate until firm and cooled.
*BEWARE*
this is really,really rich - a little bit goes a long way!