INGREDIENTS
•
Cake
•
1/2 cup unsweetened Dutch-process cocoa powder
•
2 tablespoons boiling water
•
2 ounces unsweetened chocolate, chopped
•
3/4 cup milk
•
1 cup (2 sticks) unsalted butter, softened slightly
•
2 cups sugar
•
4 large eggs, separated
•
2 teaspoons vanilla extract
•
2 cups all-purpose flour
•
1 teaspoon baking powder
•
1 teaspoon baking soda
•
1 teaspoon salt
•
Filling
•
1 tablespoon plus 1 3/4 teaspoons unsweetened Dutch-process cocoa powder
•
2 cups boiling water
•
3/4 cup plus 1/2 teaspoon sugar
•
1 ounce bittersweet chocolate, chopped
•
2 tablespoons cornstarch dissolved in 1 tablespoon cold water
•
1/4 teaspoon salt
•
1 teaspoon vanilla extract
•
2 tablespoons unsalted butter
•
Frosting
•
12 ounces semisweet chocolate, chopped
•
12 tablespoons (1 1/2 sticks) unsalted butter
•
1/2 cup hot water
•
1 tablespoon light corn syrup
•
1 tablespoon vanilla extract