This recipe offers treasures of the Caribbean “sugar islands”: chocolate, sugar, and rum. It’s a classic French buttercream using a cooked sugar technique, pâté à bombe, to blend and aerate the eggs and sugar, which creates incomparable richness. Or maybe it’s the butter. Or maybe it’s the chocolate. You get the picture—it’s rich! One batch makes enough to ice one 2-layer cake, but if you like generous layers and rosettes, double this recipe. Allow time to chill the buttercream. If soupy, chill it for another half hour. If stiff, heat it over a saucepan of hot water, then whip it. For children, you can omit the rum.

　　

Ingredients

makes 3 1/2 cups icing

　　

Chocolate Choices:

Michel Cluizel Hacienda Los Anconès or Cacao Barry Origins Saint-Domingue

　　6 large egg yolks

　　3/4 cup sugar

　　2 tablespoons light corn syrup

　　1/4 cup water

　　1 1/4 cups (2 1/2 sticks) cold unsalted butter, cut into small pieces

　　12 ounces dark chocolate, melted

　　1 tablespoon vanilla extract

　　2 tablespoons dark rum, preferably Meyers’s (optional)

　　Splash of heavy cream

　　1 teaspoon kosher salt

　　

Step 1

In the bowl of an electric mixer fitted with the whisk attachment, whip the egg yolks at medium speed for about a minute to add volume to them.

　　

Step 2

Meanwhile, in a small saucepan, stir together the sugar, corn syrup, and water. Remove any sugar crystals from the inner sides of the pan with a wet paper towel. Place the saucepan over medium heat and don’t stir anymore. Allow the mixture to boil for 2 to 3 minutes, until it reaches the soft-ball stage, or 235°F on a digital (or candy) thermometer.

　　

Step 3

Stop the mixer, take off the wire whip and do the next step by hand. Carefully add a small splash of the hot sugar mixture into the egg yolks and briskly stir with the wire whisk. Once it is fully mixed, pour in a little more hot sugar and repeat . . . slowly . . . until all of the sugar mixture is incorporated into the yolks. Place the whip and the bowl back on the mixer and whip at medium speed for about 5 minutes, or until it becomes light and fluffy. Add pieces of butter, one at a time, while continuing to whip the buttercream. Stop the mixer and add the chocolate, vanilla, rum, cream, and salt. Allow the mixture to whip for another minute and taste your creation. Adjust the flavors, then chill and rewhip a little before using.

　　Chocolate Bliss