Grease a 24cm round springform pan (base 22cm). Line base with
baking paper.
Process biscuits until crushed. Add butter and process until combined. Press mixture on base and up sides of pan. Refrigerate.
To make cheesecake filling, sprinkle
gelatine over water in a heatproof jug. Stand jug in a pan of simmering water
and stir until dissolved. Remove and cool. Place chocolate in a heatproof bowl
over simmering water. Stir until
melted. Cool for 10 minutes.
Beat cream cheese and caster sugar with an electric mixer
until smooth. On a low speed, beat in cream, chocolate and gelatine mix until
smooth. Fold in chocolate bar.
Pour over base. Cover and refrigerate
overnight until set.
To serve, remove sides
of pan. Move to a serving plate. Sprinkle
the two chocolate bars over top.