While the cream cheese is still cold from the refrigerator place it in the bowl of an electric mixer fitted with a paddle attachment and beat for a minute until softened.
Switch the mixer to it's lowest speed and add the powdered sugar and beat until combined and the mixture is smooth and creamy.
Switch the mixer off and fold through roughly 2/3 of the crushed cookies using a spoon. Refrigerate the mixture for at least an hour, preferably two.
Place the remaining crushed cookies into a small shallow bowl and line a baking tray with non stick baking paper.
Remove the mixture from the refrigerator and roll into rough balls before rolling in the crushed cookies. Roll the mixture again in between the palm of your hands and place on the baking paper. Rolling the crushed cookies helps get the surface somewhat smooth, but given the mixture is quite soft it will be difficult to form perfect balls.
Refrigerate for 30 minutes to an hour.
Melt the dark chocolate in a bowl over a saucepan of simmering water, or in the microwave.
Using two forks, or a chocolate dipper if you have one, dip the cheesecake mixture in the melted chocolate and use the forks to remove the truffle from the chocolate. Tap the fork to remove excess chocolate and place back on the baking paper to set.
Sprinkle with remaining cookies crumbs.
Refrigerate until set and then store in a sealed container.
Truffles should last a week in the refrigerator.... that is unless you eat them first!