1. Stir the butter until it's creamy (the softer the butter, the easier it will be), add the icing sugar bit by bit.
2. Mix the cream cheese and vanilla extract in a seperate bowl (one teaspoon of vanilla extract should be enough, the stuff is really strong!).
3. Last but not least, bring the two mixtures together. If you want to, you can use food colouring (like I did).