Devil’s Food Cake with Angel Frosting from Baked Explorations: Classic American Desserts Reinvented by Matt Lewis

Ingredients

• ½ cup dark unsweetened cocoa powder (like Valrhona)
• 1 ounce good-quality dark chocolate (60 to 72%), broken into a few pieces
• 5 large egg whites, at room temperature
• 1½ cups granulated sugar
• 3 large eggs
• 1 teaspoon pure vanilla extract
• 1 teaspoon vanilla paste (or 1½ teaspoons pure vanilla extract)
• 1 tablespoon light corn syrup
• 1⅓ cups all-purpose flour
• 1 teaspoon baking soda
• ⅔ cup hot coffee
• ⅓ cup whole milk
• 1 cup firmly packed dark brown sugar
• ½ cup granulated sugar
• ½ teaspoon salt
• 10 tablespoons (1¼ sticks) unsalted butter, cut into ½-inch cubes, softened