Grease and line with baking paper two 20cm (8 inch) round springform baking pans.
In a large bowl add plain flour, white sugar, cocoa, baking powder, bicarb soda and salt. Stir to combine.
Add eggs, milk, vegetable oil & vanilla extract. Using an electric beater mix until fully combined.
Add boiling water and continue beating until fully combined.
Pour batter evenly into the two baking pans.
Place in oven and cook for between 30 – 35 minutes or until a skewer inserted into the centre of the cake comes out clean.
Remove from oven and allow to cool in pans for about 10 minutes before removing the cakes from the pans, inverting them and allowing them to cool completely on wire racks.
In a large bowl, add cream cheese and icing sugar and using an electric mixer, beat until fully combined and smooth.
In a separate bowl add thickened cream and using and electric mixer, beat until stiff peaks form.
Add cream to cream cheese mixture and stir until fully combined.
Add crushed oreos and stir to mix through.
In a medium saucepan over medium heat, add milk chocolate and thickened cream.
Cook while constantly stirring until chocolate melts and mixture becomes smooth. Remove from heat and allow to cool down a little before using to apply ganache layer to cake.
Whipped Cream Piping
In a bowl add thickened cream and beat until soft peaks form
Add caster sugar, 1 tbsp at a time, and continue beating until stiff peaks form. Add caster sugar to attain your required level of sweetness.
Place one chocolate cake on a plate and spread oreo cheescake filling over the top. Spread as evenly as possible.
Place second chocolate cake on top and smooth oreo cheesecake filling to cover any gaps between the layers. Place in refrigerator for about 10 minutes or until ganache is ready, to allow cheesecake filling to firm a little.
When ganache has cooled sufficiently pour over the top pf the cake and allow some ganache to drip and run down the sides of the cake.
Place in refrigerator for about 15 minutes to allow ganache to firm.
Pipe sweetened cream onto the top of the cake and sprinkle with crushed oreo.