German Buttercream (Custard Buttercream)
5 cups (enough to frost a two layer 8-inch cake)
The combination of custard and whipped butter creates a frosting that is similar to a whipped cream icing. Light, and creamy and less sweet than American buttercream, it pairs well with chocolate and spiced cakes.
- 2 cups milk, divided
- 1 teaspoon vanilla extract
- 1/4 cup Swans Down® Cake Flour
- 3 tablespoons cornstarch
- 3/4 cup sugar
- 2 large egg yolks
- 2 cups (4 sticks) unsalted butter, room temperature
- Sifted confectioners’ sugar, to taste
- Whisk together milk, vanilla, flour, cornstarch, sugar and egg yolks in a medium heavy-bottomed saucepan, until fully combined. Cook over medium-low heat, whisking continuously, until mixture begins to simmer. Raise heat to medium and continue cooking and stirring with a heat-proof spatula to prevent sticking. Continue stirring until mixture thickens to a custard and comes to a boil.
- Pass through a strainer into a medium bowl. Place plastic wrap directly over top of the custard to prevent a skin from forming. Refrigerate for 2 hours or until set.
- Remove from refrigerator and allow to reach room temperature. Whip until the custard is smooth.
- Whisk butter in an electric mixer with whisk attachment until light, fluffy and pale in color. Add the room-temperature custard one heaping spoonful at a time, then add the whipped butter, whisking until incorporated after each addition. When all the custard has been added, taste for sweetness and flavor. Whisk in more vanilla and some confectioners’ sugar if desired.
- The buttercream can be made ahead of time and stored in an airtight container in the refrigerator for up to two weeks. Allow it to come to room temperature before whipping and using.
- The buttercream can be cooled more quickly by lining a half sheet pan with plastic wrap and spreading the warm frosting on the plastic evenly, with another sheet of plastic wrap placed directly on top. Place in refrigerator until cool, about 30 minutes.