Pre heat oven to 160'C fan or 180'C conventional
Crush 200g of oreos and mix with the melted butter. Compress evenly in your tray and place in the freezer for 30mins
Mix your cream cheese, sour cream, icing sugar, corn flour, and vanilla. Roughly chop 5-6 oreos and fold these into the mix
Pour into your tray and place in to the preheated oven for 40-45 minutes. You'll know when it's done when the surface has turned lightly golden and the centre 2" still has a slight wobble.
Now, leaving your cheesecake inside, turn your oven off and leave the door shut, allow to cool for 1hr
Remove from the oven and allow to cool completely
Crush your remaining oreos and sprinkle on top
Optional: Refrigerate for a minimum of 2 hours for best results