PERFECT CHOCOLATE FROSTING

75 g butter
175 g good quality chocolate
300 g confectioners sugar
1 Tbsp vanilla extract
40 g dark unsweetened cocoa
125 g sour cream

In a bowl hanging ( but mot touching) over boiling water melt butter and chocolate. When it has melted and cooled a bit mix in rest of the ingedients. The consistency should be that of a thick spread, not too runy (then add cocoa) and not too stiff (then add boiling water).
This is a wonderfull not too sweet chocolate frosting that makes the perfect finish on any kind of fluffy cake. I just can’t stop trying the frosting to make sure that I haven’t immagined it.