Crush up Oreo cookies in food processor until fine.
Add 3 tbsp of melted butter. Mix until well combined.
Add cookie mixture into cake pan and evenly spread out until the bottom of the cake pan is covered.
Freeze cookie crust for about 15 minutes (or until firm).
For Cheesecake Filling:
Whip cream cheese with hand mixer until creamy.
Add tub of whipped topping to cheesecake mixture and mix until creamy.
Add vanilla extract and sugar and mix until combined.
Add 1 tablespoon of unflavored gelatin with 2 tablespoons of hot water and mix until gelatin is dissolved. Add mixture to cheesecake mixture and combine with hand mixer.
Roughly chop remaining Oreo cookies and fold into cheesecake mixture.
To finish Cheesecake:
Take cookie crust out of the freezer.
Spray the sides of the cake pan with non-stick spray or line with parchment paper (to avoid the sides of the cheesecake sticking to the pan!)
Pour cheesecake filling into the cake pan and spread out evenly.
Cover with plastic wrap and chill in the refrigerator for 4-6 hours.