Preparation Steps

• Preheat the oven to 375°F (190°C). Line 3 baking sheets with parchment paper.
• In a medium bowl, whisk together flour, salt, baking soda, ground ginger, cinnamon, and nutmeg. Set aside.
• In a large bowl, beat vegetable shortening, softened butter, and brown sugar until smooth and fluffy.
• Add the egg to the butter mixture and beat until well incorporated.
• Add half of the dry flour mixture to the wet ingredients and mix to combine.
• Mix in the molasses, remaining dry ingredients, and buttermilk until fully combined.
• Drop 1 tablespoon of dough onto the prepared baking sheets, leaving 2 inches between each dollop. For larger cookies, use 1/4 cup of dough.
• Bake cookies for 12 to 15 minutes or until a toothpick inserted in the center comes out clean.
• Remove cookies from oven and transfer baking sheets to a wire rack to cool completely.
• To prepare the vanilla buttercream filling, beat softened butter on high speed until light and fluffy, about 1 minute.
• Gradually add powdered sugar, 1/2 cup at a time, mixing on low speed until combined.
• Pour in milk and vanilla extract, then beat on high until the frosting reaches your desired consistency. Add more milk if needed.
• Spread frosting on the bottom side of one cooled cookie and sandwich with another cookie on top.