Beat the softened butter to a soft and even consistency. Add the orange juice, if using, then the icing sugar. Cream until you have a smooth, soft buttercream consistency.

Add the cream cheese and work it in – don’t beat it in, just slowly mix with a wooden spoon. Depending on how soft the mixture is, you may want to put it in the fridge for 10 mins at this point. If it’s runny, it will firm up again. It should be spreadable and not run off the cake.