Grease 4 round cake rings or ramekins.
Put the cookies in a bowl and crush them with a pestle or a rolling pin until you get fine crumbs. Pour the melted butter over the crumbs and mix well.
Spoon this mixture into the prepared rings (placed on a tray) or ramekins and rest them in the fridge.
Finely chop the chocolate, set aside.
Pour some boiling water in a small bowl. Add the mint and soak for a minute. Rinse with cold water, then squeeze out the water through a fine sieve, first using a spoon, then your hand.
Put the mint, soft cheese and icing sugar in a small food processor. Pulse for a couple of minutes until well combined.
In a mixing bowl, whisk the double cream until soft peaks form.
Fold in the cheese mixture, then the chopped chocolate.
Divide this mixture evenly between the rings - then chill for at least 4 hours or overnight.
Carefully remove the rings, then serve, garnished with some mint leaves.