Ingredients

makes enough for one tiered wedding cake (about 5 cups)

　　3 tablespoons instant espresso powder

　　3 tablespoons hot water

　　6 large whole eggs, plus 6 large egg yolks

　　2 cups sugar

　　6 cups whole milk

　　1 1/2 vanilla beans, split lengthwise and seeds scraped

　　1 cup plus 2 tablespoons cornstarch

　　3/4 teaspoon salt

　　6 tablespoons unsalted butter, cut into small pieces

　　6 ounces bittersweet chocolate, coarsely chopped

　　

Step 1

Prepare an ice bath; set aside. In a small bowl, combine the espresso powder and hot water, and stir until dissolved; set aside. In a medium bowl, combine the whole eggs, egg yolks, and 1 cup sugar. Whisk to combine.

　　

Step 2

In a medium saucepan, combine the milk, vanilla seeds, cornstarch, salt, and remaining cup of sugar. Bring to a boil over medium-high heat, whisking constantly. Remove from the heat; slowly pour about a third of the hot milk mixture into the egg mixture, whisking constantly until combined. Pour egg mixture back into the remaining milk, whisking constantly. Return saucepan to medium-high heat. Bring to a boil, whisking constantly, until mixture is thick enough to hold a trail when you drag a wooden spoon through it, about 3 minutes.

　　

Step 3

Whisk in butter, one piece at a time. Whisk in chopped chocolate and espresso mixture; continue whisking until smooth and combined. Strain the mixture into a large, heatproof bowl. Cover with plastic wrap, pressing it directly onto the surface to prevent a skin from forming. Place in the ice bath until completely chilled, stirring occasionally, about 30 minutes. Cover and refrigerate until ready to use, up to 3 days.

　　Reprinted with permission from Martha Stewart's Baking Handbook by Martha Stewart. © 2005 Clarkson Potter