INGREDIENTS
•
10 tablespoons unsalted butter, plus additional for cake pans
•
1/2 teaspoon baking soda
•
1 teaspoon kosher salt
•
1 1/2 teaspoons baking powder
•
2 1/2 cups all-purpose flour
•
2 eggs
•
1 1/3 cups granulated sugar
•
2 teaspoons vanilla extract
•
2 cups sour cream
•
1 1/2 cups coarsely chopped semisweet chocolate
•
5 tablespoons cool water, plus more for the double boiler
•
1/4 teaspoon cream of tartar
•
1 1/3 cups granulated sugar
•
2 egg whites, room temperature
•
1 tablespoon light corn syrup
•
1 teaspoon vanilla extract