Preheat oven to 150˚C.
Line cupcake pan with cases.
Add the milk chocolate and butter to a saucepan.
Melt, over low heat while stirring continually.
Add the plain flour to a large mixing bowl.
Slowly beat in the milo and brown sugar.
Add the four beaten eggs and vanilla essence and mix well.
Add the chocolate/butter mix and beaten until smooth.
Fill 12 cupcake cases 3/4 full and bake for around 20 mins.
Once cool, top with chocolate buttercream icing.