Fourth of July Whoopie Pies

Ingredients

• 2 1/4 cups of all purpose flour
• 1 1/2 teaspoons of baking powder
• 1/2 teaspoon of salt
• 4 Tablespoons of unsalted butter at room temperature
• 4 Tablespoons of vegetable shortening
• 1/2 cup granulated sugar
• 1/2 cup brown sugar
• 2 large eggs at room temperature
• 1/2 cup of buttermilk
• 2 Tablespoons of milk
• 1 teaspoon of baking soda
• 1 teaspoon of white vinegar
• 1 teaspoon of vanilla extract
• Red icing coloring
• Blue icing coloring
• 2 sticks of butter at room temp
• 3-4 cups of powdered sugar, sifted
• 1 Tablespoon of vanilla extract