2 cups cake flour (see Cook?s Note)
3/4 cup Dutch-process cocoa powder (see Cook's Note)
1 1/2 cups granulated sugar
1 teaspoon baking powder
1 teaspoon baking soda
1/2 teaspoon kosher salt
3/4 cup buttermilk, at room temperature
3/4 cup warm coffee
1/2 cup vegetable oil
2 large eggs, at room temperature
1 teaspoon pure vanilla extract
6 ounces semisweet chocolate chips or semisweet chocolate (64-percent cacao), chopped
2 sticks (16 tablespoons) unsalted butter, at room temperature??
1/2 teaspoon kosher salt??
1 cup confectioners' sugar
2 teaspoons Dutch-process cocoa powder?
1 1/2 teaspoons pure vanilla paste or extract?
When measuring flour, we spoon it into a dry measuring cup and level off excess. (Scooping directly from the bag compacts the flour, resulting in dry baked goods.) We like Dutch-process cocoa for our chocolate cake because it adds a deep, mellow chocolate flavor, but regular cocoa powder will also work. The flavor will just be slightly fruity and more acidic.