Boston Cream Whoopie Pies Recipe: How to Make It

Ingredients

• 6 tablespoons sugar
• 3 tablespoons cornstarch
• 1/4 teaspoon salt
• 1 cup 2% milk
• 6 tablespoons heavy whipping cream
• 1 large egg yolk, beaten, room temperature
• 2 teaspoons vanilla extract
• COOKIES:
• 9 tablespoons butter, softened
• 1 cup sugar
• 2 large egg yolks, room temperature
• 1 large egg, room temperature
• 1/2 teaspoon grated lemon zest
• 1 cup plus 2 tablespoons cake flour
• 1 cup all-purpose flour
• 3/4 teaspoon baking soda
• 1/2 teaspoon salt
• 1/2 cup plus 2 tablespoons buttermilk
• GLAZE:
• 2 ounces unsweetened chocolate, chopped
• 4 teaspoons butter
• 1/2 cup whipping cream
• 1 cup confectioners' sugar