Professional-Style Buttercream Made with Egg Yolks

This is the buttercream recipe used by most professionals. You make a sugar syrup and cook it to the soft-ball stage, and although it isn’t difficult, you do need to arm yourself with a small metal spoon and a bowl of cold (but not iced) water. As the sugar syrup boils, you dip the spoon handle in the syrup and then immediately into the water. When the syrup hardens to the texture of chewing gum that has been chewed a bit, soft-ball stage on a candy thermometer (234°F to 240°F), the syrup i