Chocolate Marshmallow Whoopie Pies

INGREDIENTS

For the cookies:

3 1/2 cups

all-purpose flour

1 tsp

salt

1 1/2 cups

unsweetened cocoa powder

1 tbsp

baking soda

1 tsp

baking powder

1 cup

unsalted butter, room temperature

2 cups

sugar

large eggs

2 cups

buttermilk, at room temperature

2 tsp

vanilla extract

For the filling:

1 cup

unsalted butter, at room temperature

2 cups

confectioners’ sugar, sifted

7 1/2 oz

marshmallow fluff

2 tsp

vanilla extract