The perfect chocolate icing

This recipe book is the place where the perfect chocolate icing recipe is stored. It works every time I use it, and I always get comments from people about how good the icing tastes!
This is a book that my mum used to use which her mum gave to her, which explains why it looks a bit battered! If you looked inside, you'd see random numbers and adaptations to recipes on a lot of the pages!

Here's the recipe: 

65g (2.5oz) butter

45ml (3tbsp) milk

25g cocoa powder (1oz) (sieved)

225g icing sugar (8oz) (sieved)

1. First, you need to weigh the butter in milk into a pan, place on a low heat and the wait until the butter has melted.
2. Whilst you're waiting for the butter to melt, sieve the icing sugar into a large bowl. I don't often sieve things, but I've worked out that to get the perfect icing sieving is necessary for this recipe.
3. Weigh out the icing sugar into a smaller bowl. 
4. If the milk gets too hot then the mixture can sometimes split so take the pan off the heat as soon as the butter has melted. Pour the melted butter mixture into the bowl with the cocoa and stir. (Do not try it at this stage! Note : melted butter and cocoa do not taste good!)
5. Next, add the icing sugar bit by bit ensuring that you sieve it. Mix into the cocoa, milk and butter mixture until all the icing sugar is added. At some points it'll seem as if the mixture is too runny or too thick, but don't worry! It will come together!

Different ways of using the icing:

In order to sandwich, ice and cover the three layered 7 inch cake the recipe needs to be doubled. 

This icing can be used immediately for a smooth, glossy finish on top of the cake. However, I've found that for the cake to stay in place then you need to allow the icing to cool and thicken which makes it easier to spread and gives it more of a buttercream texture and consistency

This chocolate icing is perfect on the three layered 7 inch sandwich chocolate cake and allows the cake to simple so that you can focus on the show stopper decorations!