Bailey’s Chocolate Whoopie Pies

Ingredients

• 1 cup buttermilk
• 1/2 cup unsalted butter
• 3/4 cup unsalted butter
• 1 teaspoon vanilla extract
• 1 teaspoon sea salt
• 2 cups all-purpose flour
• 4 1/2 cups powdered sugar
• 1 teaspoon espresso powder
• ½ cup unsweetened cocoa powder
• 1 cup light brown sugar
• 1 ¼ teaspoons baking soda
• 1 large egg
• 6 tablespoons Baileys Irish Cream Liqueur