I came across it in the 2010 issue of Donna Hay Kids (Issue 7).
Donna Hays Basic Vanilla Butter Icing
250gm butter, softened
2 cups icing sugar
2 tablespoons milk
1 teaspoon vanilla essence
Place the butter in the bowl of an electric mixer and beat for 6-8 minutes or until pale creamy.
Add food colouring if desired.
It is so smooth and creamy, pipes out of an icing bag beautifully (I used a number 12 Wilton nozzle in case you're interested) and keeps well due to its high butter content.