INGREDIENTS:

• 2 egg yolks
• 60 g caster (superfine) sugar
• pinch of salt
• 125 ml double (thick) cream, scalded
• 2,5 ml (1/2 tsp) vanilla essence
• 250 g unsalted butter

INSTRUCTIONS:

Beat the egg yolks wich the sugar and salt, and slowly pour over the scalded cream, stirring constantly Put (lie mixture in (he (op pan of a double boiler or into a heatproof bowl and sit it over, not in, simmering water. Cook, stirring constantly, until the mixture coats a metal spoon. Remove the pan from the heat and add the vanilla essence. Set aside until cool.

Beat the butter until it is fluffy and add it, a little at a time to the custard. You have to do this carefully, or the mixture may curdle.
You can change the flavour by adding some melted plain (semisweet) chocolate, or omit the vanilla and add a liqueur of your choice.

This will generously cover the top and sides of a 23-cm (9-in) cake.

Free Download Prinable Custard-Based Buttercream Icing Recipe (PDF) 

https://drive.google.com/open?id=1NGAbj6XVw8PZRgU1amqiWPAF2Oob8wtN