Recipe makes about 18 medium pies.

Whatcha Need for the Cakes:
1-2/3 cups all purpose flour
2/3 cup unsweetened cocoa powder
1-1/2 tsp baking soda
1/2 tsp salt
4 Tbsp unsalted butter (room temperature)
4 Tbsp vegetable shortening
1 cup brown sugar (packed)
1 large egg
1 tsp vanilla extract
1-1/4 cup milk

Whatcha Need for the Filling:
1-1/2 cup Marshmellow Fluff*
1-1/4 cup vegetable shortening
1 cup confectioners’ sugar
1 Tbsp vanilla extract

Whatcha Do

1. Position rack in center of the oven; preheat to 375 degrees F. Line two baking sheets with parchment paper.
2. Sift together flour, cocoa powder, baking soda, and salt. Set aside.
3. In the work bowl of a stand mixer, using the paddle attachment, beat butter, shortening and brown sugar on low speed until just combined. Increase speed to medium and continue to beat for 3 minutes longer. Add egg and vanilla and beat an additional 2 minutes.
4. Add half of the flour mixture and half of the milk to batter. Beat briefly on low. Beat in remaining flour mixture and milk.
5. Using a #50 ice cream scoop, drop batter 1 scoop at a time onto the baking sheets, spacing about 2 inches apart. Bake one sheet at a time for about 10 minutes or until pies spring back when pressed gently. Remove from oven and cool on the sheet for 5 minutes before transferring to a rack to finish cooling.
6. To make the filling: Beat marshmallow fluff and shortening for 3 minutes on medium. Reduce speed to low and add sugar and vanilla. Beat until incorporated. Increase speed to medium; beat until fluffy.
7. Sandwich filling between the flat sides of two pies, repeating until all pies are filled.

*Marshmallow Fluff may not be available in all markets. You may substitute marshmallow creme by adding a bit more sugar to the mix to ensure the filling is stiff enough.