S’mores Whoopie Pies

These delicious and easy S’mores Whoopie Pies pack all the flavors you love about the iconic campfire treats. The whoopie pies feature soft graham cookies sandwiched around a layer of chocolate ganache and a creamy marshmallow filling. You’ll enjoy these year-round!

What Are Whoopie Pies, Exactly?

They’re not quite cakes, they’re not quite cookies, and they’re definitely not pies; but they are delicious! From the classic chocolate and marshmallow fluff to gourmet and savory varieties, the sky is the limit when it comes to flavor combinations. Throw in that they are portable and easy to eat without a plate or silverware, and you can begin to see why they have become so popular.

By now you know that I’m a born-and-bred Pittsburgh girl, and whoopie pies were known as gobs when I was growing up. And they only came in one flavor - chocolate with a white icing center. They sent my little heart racing.

My mom had a couple of friends that could make really sensational gobs and I always looked forward to the parties where they would show up. Now, that there are so many possibilities at my fingertips, look out!

Skip the Campfire and Make These Cookies Instead

These s’mores whoopie pies are as close to a s’more as you can get without the actual graham cracker and ooey-gooey marshmallow. The cake part is made with graham flour, which imparts that classic graham cracker flavor. I made them for the 4th of July weekend, and they were a hit! They’re also perfect for fall or winter when you crave campfire cooking (but don’t want to actually fool with a campfire).

The recipe comes from the Whoopie Pies cookbook, which was co-authored by Sarah Billingsley and Amy Treadwell. Sarah is a native of Pittsburgh and used to write for the local newspaper, the Pittsburgh Post-Gazette. I worked with the food editor there to write a piece about the popularity of whoopie pies, their history, and a bit about Sarah and the book. The article includes recipes for Tiramisu Whoopie Pie and the Jalapeño Cornbread Whoopie Pie.

Wanting to make real s’mores? Try my homemade marshmallows when you do!

Key Ingredients

This homemade s’mores whoopie pie recipe is threefold - the graham cracker whoopies, the classic marshmallow filling, and the chocolate ganache.

For the two cakey cookies, you’ll need:

• All-purpose flour and graham flour (I like to use the Bob’s Red Mill brand of graham flour you should be able to find in the organics section of the local supermarket.)
• Baking powder and baking soda
• Salt
• Butter (unsalted and at room temperature)
• Vegetable shortening
• Dark brown sugar (for the stronger molasses flavor and the deeper brown color, but you could use light brown sugar in a pinch)
• Large eggs (also at room temperature)
• Buttermilk and milk
• White vinegar
• Pure vanilla extract

For the creamy marshmallow filling, you’ll need:

• Marshmallow Fluff (or other prepared marshmallow cream, which will do in a pinch)
• Vegetable shortening
• Confectioners' sugar (aka powdered sugar)
• Pure vanilla extract

And, lastly, for the velvety smooth chocolate ganache, all you’ll need is milk chocolate chips (or a finely chopped solid chocolate bar) and some heavy cream.

What’s the Difference Between Graham Flour and Whole Wheat Flour?

These two flours look super similar but are intrinsically different. Graham flour is technically a type of wheat flour, and it can be considered whole wheat. The difference between graham flour and regular whole wheat flour, however, is that the components of the wheat grain, the bran, germ, and endosperm are separated and ground separately.

All the parts of the grain remaining in their original proportions means that graham flour is a whole wheat flour, and the names are sometimes used interchangeably. But it’s important to note that regular whole wheat flour is not a direct substitute for graham flour. (But for the sake of yielding a brown-toned whoopie pie, it could be used if you’re unable to find graham flour).

How To Make the Whoopies

1. Prep: Position a rack in the center of your oven (to ensure even baking), and preheat it to 375 degrees F. Line two baking sheets with parchment paper, and set aside.
2. Make the Whoopie Batter: In a medium bowl, stir together both flours, baking powder, and salt. Next, in the bowl of a stand mixer fitted with the paddle attachment, beat together the softened butter, shortening, and brown sugar until light, creamy, and fluffy. Add the eggs one at a time, along with the buttermilk, and beat until combined. Then, combine the milk, baking soda, and vinegar in a measuring cup before adding it to the other wet ingredients, followed by the flour mixture. Beat on low until just combined. Add the vanilla extract, and beat on medium speed for about 2 minutes, until completely combined.
3. Bake the Whoopies: Using a spoon, drop approximately 1 tablespoon of batter onto one of the prepared baking sheets and repeat, spacing them at least 2 inches apart. Bake one sheet at a time for about 10 minutes each, or until the cakes begin to brown. Remove from the oven and let the cakes cool on the sheet for at least 5 minutes before transferring them to a rack to cool completely.

How To Make Chocolate Ganache

Put the chocolate in a large, heatproof bowl. Heat the cream in a large saucepan over medium heat just until it bubbles (aka scalding the cream). Pour the hot cream over the chocolate in the bowl, and let it sit for about 10 minutes, until the chocolate is completely melted. Stir with a wooden spoon or spatula until smooth.

Allow the mixture to rest at room temperature until firm enough to spread, about 2 hours. You may also refrigerate the mixture for about 30 minutes, until it is firm enough to spread, stirring every 10 minutes.

How To Make the Classic Marshmallow Filling

In the work bowl of a stand mixer fitted with the paddle attachment, beat together the Marshmallow Fluff and the vegetable shortening, starting on low and increasing to medium speed until the mixture is smooth and fluffy, about 3 minutes.

Reduce mixer speed to low, add the confectioners' sugar and the vanilla, and beat until incorporated. Increase mixer speed to medium and beat until fluffy, about 3 minutes more.

How To Assemble the Whoopie Pies

Pipe or spread a layer of chocolate ganache filling onto the flat side of one of the cakes. Using the same method, top the chocolate filling with the marshmallow filling. Top it with another cake, flat-side down.

Repeat with the rest of the cakes and filling. Serve, and enjoy!

Tips and Variations

• I know many people are opposed to vegetable shortening, but it really is a necessary ingredient for these homemade whoopie pies. It gives the cakes their characteristic lift and lightness, and the rounded shape. It is also a crucial component of the classic marshmallow filling. I can attest to both of these after reviewing my mom's old recipes for gobs
• Make sure the whoopies are completely cooled before sandwiching them with the marshmallow and chocolate ganache fillings. Otherwise, they’ll spread and not adhere to the whoopies.
• Garnish these homemade whoopie pies with a drizzle of the chocolate ganache and some crumbled graham crackers to give them even more s’mores vibes!

Storage, Freezing, and Reheating Instructions

• Store these s’mores whoopie pies at room temperature in an airtight container or plastic bag for up to 5 days.
• Freeze these fully prepared desserts in an airtight, freezer-safe container or plastic bag for up to 1 month.
• Reheat these from frozen by simply letting them thaw to room temperature.

More Sandwich Cookies To Try

• Classic Whoopie Pies
• Red Velvet Whoopie Pies
• Peppermint Whoopie Pies
• Pumpkin Whoopie Pies with Maple Cream Cheese Frosting
• Homemade Oatmeal Cream Pies

Photography by Dee Frances.