Source: Rose Levy Beranbaum's Rose's Heavenly Cakes
Silk Meringue Buttercream
Makes about 5 1/2 cups
1/2 cup sugar (3.5 oz)
5 large egg yolks, at room temperature
1/2 cup canned coconut milk
1 tsp vanilla extract
1 tsp coconut extract
Make the Crème Anglaise: Have ready a fine-mesh strainer suspended over a medium bowl.
In a medium heavy saucepan, combine the sugar and yolks.
In a small saucepan, bring the coconut milk to a boil. Add 2 Tbsps to the yolk mixture, stirring constantly. Gradually stir in the remaining coconut milk and cook over medium-low heat, continuing to stir constantly, just until below the boiling point. Themixture will start to steam slightly and an instant-read thermometer will register 170 degrees F/ 76 degrees C. Immediately pour the coconut milk through the strainer, scraping up any clinging to the bottom of the pan. With the back of a spoon or silicone spatula, press the mixture through the strainer into the bowl. Cool, stirring occasionally. Stir in the vanilla and coconut extract. (To speed cooling, put the bowl inside another bowl partially filled with ice water.)
Set a piece of plastic wrap, coated lightly with nonstick cooking spray, directly onto the surface of the crème anglaise to keep a skin from forming. Refrigerate for up to 5 days, or until ready to complete the buttercream.
2 large egg whites, at room temperature
1/3 cup plus 2 Tbsp, divided, superfine sugar
1 Tbsp water
1/4 tsp cream of tartar
Make the Italian Meringue: Heave ready a 1-cup or larger heatproof glass measure.
Place egg whites in the bowl of a stand mixer fitted with the whisk attachment, or in a medium bowl and have ready a handheld mixer.
In a small heavy saucepan, preferably non-stick, stir together the 1/3 cup of sugar and the water until all the sugar is moistened. Heat on medium-high, stirring until the sugar dissolves and the mixture is bubbling. Stop stirring and reduce the heat to low. (On an electric range, remove the pan from the heat.)
Beat the egg whites on medium speed until foamy. With the mixer off, add the cream of tartar. Raise the speed to medium-high and beat until soft peaks form when the whisk is raised. Gradually beat in the remaining 2 Tbsp of sugar until stiff peaks form when the whisk is raised slowly.
Increase the heat under the sugar syrup to medium-high and boil for a few minutes until an instant-read thermometer registers 248-250F/120C (firm ball stage). Immediately transfer the syrup to the glass measure to stop the cooking.
If using a stand mixer, with the mixer off to keep the syrup from spinning onto the sides of the bowl, add the syrup to the egg whites. Begin by pouring in a small amount of the syrup. Immediately beat on high speed for 5 seconds. Add the remaining syrup in the same way in three parts. For the last addition, use a silicone spatula to remove the syrup clinging to the glass measure and scrape the syrup off against the beater. If it has hardened before most of it has been poured, soften it to pouring consistency for a few seconds in the microwave.
If using a handheld mixer, beat the syrup into the egg whites on high speed in a steady stream. Don’t allow the syrup to fall on the beaters or they will spin it onto the sides of the bowl.
Lower the speed to medium and continue beating for 2 minutes. If you don’t have a second mixer bowl, transfer the Italian meringue to another bowl.
Completed Silk Meringue Buttercream
4 sticks unsalted butter
2 Tbsp. CocoRibe (optional)
2 3/4 cup, fresh or thawed and towel-dried frozen coconut, finely grated, loosely packed
Complete the Buttercream: In the bowl of a stand mixer fitted with the whisk beater, beat the butter on medium speed for 30 seconds, or until creamy. Gradually beat in the crème anglaise until smooth. Add the Italian meringue and beat until just incorporated. If the mixture looks curdled instead of smooth, it is too cold. Allow it to sit at room temperature to warm to 70F before continuing to beat, or suspend the bowl over a pan of simmering water and heat very briefly, stirring vigorously when the mixture just starts to melt slightly at the edges. To stop the warming, dip the bottom of the bowl into a larger bowl filled with ice water for a few seconds to cool it. Remove the bowl from the ice water and beat the buttercream by hand until smooth. Beat in the CocoRibe, if using, and 2 cups of the coconut.
Use the buttercream to frost the cake or transfer to an airtight bowl until ready to use.
Highlights for Success:
- Use whole (not light) coconut milk
- Use “natural” coconut extract available at health food stores