1. Mix the biscuit crumbs with the butter, then line the bottom and sides of a 26cm springform tart pan evenly to form a crust. Set aside in the fridge.
2. Dissolve the gelatine in 30ml cold water in a bowl and leave to set. Then melt it carefully by putting the bowl in a larger bowl of boiling water and stirring gently until runny.
3. Beat the caramel and cream together until smooth. Beat in the melted chocolate until just mixed. Lastly, add the melted gelatine. Pour the batter into the prepared crust and refrigerate until set. Garnish with fresh mint leaves, chocolate biscuits and shards.