Instructions

1. Lightly grease a 9 inch (23 cm) springform baking tin with a little butter and set aside. Add your Oreo biscuits (cream and all) to a food processor and blend until they resemble fine crumbs. Melt your butter in the microwave and then pour over your crushed Oreos and whiz again until the mixture resembles wet sand. Pour your Oreo mixture into your prepared tin and press down gently to form an even layer. Pop in the fridge.
2. Place your marshmallows in a heatproof bowl and pop on top of a saucepan filled with a small amount of water, ensuring the bottom of the bowl will not touch the water below. Place on a medium-low heat and stir gently as the marshmallows slowly start to melt. Once they are slightly melted, add the milk and continue to stir until smooth.
3. Meanwhile, beat your cream until soft peaks form using an electric mixer. Once the marshmallow mixture is smooth (it’s ok if there are a few small marshmallow lumps), stir in the chocolate pieces until combined. Remove from heat and gently fold through your whipped cream. Pour the chocolate marshmallow mousse over your Oreo crust, cover with a piece of alfoil and place in the fridge overnight or for at least 6-8 hours.
4. Once your mousse cake has set, gently run a knife around the edge of your tin and remove the edge. Then make your chocolate ganache, by warming your cream in the microwave until hot to the touch (but not boiling), then add your chocolate and whisk until smooth. Leave for 10-15 minutes to cool and thicken slightly. Pour your chocolate ganache over your cake and gently spread out with a small spatula, then scatter over your Kit Kats. Place in the fridge until you are ready to serve.