– 1 ½ cups flour – 2 tablespoons cornstarch – 1 teaspoon salt – ½ teaspoon baking powder – ½ teaspoon baking soda – 1 large egg – ¼ cup sugar – ¼ cup salted butter, softened, plus more for serving – 1 teaspoon vanilla extract – 1 cup half-and-half – ½ cup buttermilk – cooking spray – pure maple syrup, and/or chocolate chips, for serving