Grease and line a 20cm square baking tin with baking paper and set aside.
Roughly chop the Oreos by pressing Turbo for 1-2 seconds. Set aside.
Break the chocolate into the Thermomix bowl and grate for 10 seconds, Speed 9. Set aside.
Place the sweeteend condensed milk into the Thermomix bowl and heat for 5 minutes, 100 degrees, Speed 3.
Add the grated chocolate and heat for 3 minutes, 80 degrees, Speed 4.
Stir through the chopped Oreos with a spatula (reserving a little for decorating).
Quickly pour the mixture into the prepared tin and spread out with a spoon. Sprinkle over the remaining chopped Oreos to decorate.
Place into the fridge for 2 hours or until set.