Grease and line an 18X28cm baking tin with baking paper and set aside.
Crush the Oreo cookies until they resemble crumbs. Mix through the melted butter.
Press into the prepared tin and smooth down with a spoon. Place into the fridge.
Beat together the cream cheese, caster sugar and vanilla extract until smooth and creamy.
Beat through the cream, dissolved gelatine and cooled melted chocolate.
Add a few of the mini Oreos (slightly broken) and mix through with a spoon.
Spread the mixture over the top of the prepared base. Top with the mini Oreos and place into the fridge for 3-4 hours or until set.
Cut into pieces and store in an airtight container in the fridge for up to 1 week.