Mini Chocolate Whoopie Pies

INGREDIENTS

• 1 3/4 cups all-purpose flour
• 3/4 cup unsweetened Dutch-process cocoa powder
• 1 1/2 teaspoons baking soda
• Coarse salt
• 1/4 cup vegetable shortening
• 1/2 cup granulated sugar
• 1/2 cup packed dark-brown sugar
• 1 tablespoon unsalted butter, room temperature
• 1 large egg
• 1 cup whole milk
• 1 teaspoon pure vanilla extract
• Whipped Ganache