How Do I Fix Soupy Swiss Meringue Buttercream?

How Do I Fix Soupy Swiss Meringue Buttercream?

It’s a moment of pure baking panic. You’ve patiently heated your egg whites and sugar, whipped them into a glorious, glossy meringue, and started adding the butter. But instead of transforming into a silky, pipeable dream, your mixture collapses into a greasy, soupy mess. It looks like melted ice cream, and your heart sinks.