Step 1: Make the Chocolate Whoopie Pies

1. Preheat the oven to 350°F (175°C) and line a baking sheet with parchment paper.
2. In a bowl, whisk together the flour, cocoa powder, baking soda, and salt. Set aside.
3. In a separate small bowl, mix the buttermilk, vanilla extract, and hot water or coffee.
4. Using a hand mixer, beat the butter and sugar until light and fluffy. Add the egg and mix until combined.
5. Gradually add the dry ingredients and the buttermilk mixture, alternating between the two, until a thick batter forms.
6. Drop spoonfuls of batter onto the baking sheet, spacing them about 2 inches apart.
7. Bake for 10–12 minutes, until the cakes spring back when touched. Let cool completely.

Step 2: Make the Marshmallow Filling

1. In a large bowl, beat the butter and powdered sugar until fluffy.
2. Add the marshmallow fluff and vanilla extract, mixing until smooth.
3. Fold in the crushed graham crackers.

Step 3: Assemble the Whoopie Pies

1. Spread or pipe a generous amount of marshmallow filling onto the flat side of one chocolate cake.
2. Place another cake on top, gently pressing down to create a sandwich.
3. Optional: Roll the edges in additional crushed graham crackers for extra crunch.

Step 4: Let Them Set and Enjoy!

• Let the whoopie pies sit for at least 30 minutes to allow the flavors to meld. Store in an airtight container at room temperature for up to 3 days.