Gooey S'mores Sandwich Cookies Recipe

S'mores are the quintessential campfire snack. With just three simple ingredients, you get a gooey dessert that is so delicious. If you're craving s'mores but aren't going on a camping trip anytime soon, then this gooey s'mores sandwich cookie recipe is for you! Created by recipe developer Jessica Morone, these sandwich cookies combine two perfectly baked graham cracker cookies with gooey, toasted marshmallow buttercream and rich, whipped chocolate ganache sandwiched between them. "Theres something about s'mores that just makes them the perfect summer dessert. It always makes me think of summer camp and warm nights outside," Morone says. 

According to Morone, the best thing about these cookies is the marshmallow buttercream. She notes that "it's so fun that you can get the toasty marshmallow flavor by just using the broiler setting on your oven to toast the marshmallow creme." The toasted flavor of the marshmallow buttercream gives you the nostalgic flavor and gooeyness of s'mores, and with this cookie recipe, you can have s'mores flavors all year round!

To make these sandwich cookies, first you will gather all of the ingredients. You are going to make three components: graham cracker cookies, whipped chocolate ganache, and toasted marshmallow buttercream. For the cookies, you will need graham cracker crumbs, granulated sugar, brown sugar, baking soda, baking powder, salt, butter, an egg, and vanilla extract. "To get graham cracker crumbs, you can either put the graham cracker sheets in a food processor and pulse until you have crumbs, or put them in a ziplock bag and crush them with something heavy like a rolling pin," says Morone. "Some stores also just sell boxes of graham cracker crumbs, which is even easier!" 

For the whipped ganache, you will need heavy whipping cream, semi-sweet chocolate, and vanilla extract. For the toasted marshmallow buttercream, you will need a jar of marshmallow creme, butter, powdered sugar, and some more vanilla extract.

Line two baking sheets with mats or parchment paper. Set aside.

In a large bowl, whisk together the graham cracker crumbs, granulated sugar, brown sugar, baking soda, baking powder, and salt.

Add the melted butter, egg, and vanilla extract to the bowl, and mix until a soft dough forms.

Scoop out 1 tablespoon of dough at a time and roll the dough between your hands to form balls. Place on the prepared baking sheets, and refrigerate for at least 30 minutes or freeze for about 10 minutes.

Preheat the oven to 350 F.

Bake the cookies in the oven for 8–10 minutes, until golden brown on the edges. Let cool completely.

Meanwhile, heat the heavy cream in a saucepan until it just starts to steam.

Pour the heated cream over the chopped chocolate in a medium bowl. Let sit for at least 1 minute.

Whisk the cream and chocolate mixture until it comes together and becomes shiny. Refrigerate for 15–30 minutes, until it cools and thickens.

Once cooled, add the ganache to the bowl of a stand mixer with the vanilla extract. Whip until the ganache becomes light and fluffy. Set aside.

Set your oven to broil.

Spread the marshmallow creme in a thin layer on a baking sheet lined with parchment paper, then set aside.

In the bowl of a stand mixer, beat the butter until smooth.

Add the powdered sugar and vanilla extract, and beat until light and fluffy.

Place the baking sheet with marshmallow creme under the broiler and heat for 1–2 minutes, until golden brown on top. Watch carefully, as this can happen very quickly!

Scrape the toasted marshmallow creme into the stand mixer and beat until the mixture becomes smooth. The frosting will likely first separate from the warm marshmallow but will come together again as you keep beating it. Let cool completely.

Pipe or spread the marshmallow buttercream onto the bottom of half of the cookies.

Pipe the whipped ganache on top of the marshmallow buttercream.

Place the remaining cookie halves on top to make cookie sandwiches, then serve!

Marshmallow creme (of fluff) can be found at pretty much any grocery store, but there are some options if you want to try something else. The easiest substitute for using marshmallow creme in this recipe is to use mini marshmallows. Spread 3 cups of mini marshmallows out on a baking sheet lined with parchment paper and broil the pan in the oven for about 45 seconds, until they get brown and puffy. Another option is to use regular-sized marshmallows — you can use about 24 regular-sized marshmallows for every 3 cups of mini marshmallows, but Morone notes that "the larger marshmallows won't toast as quickly under the broiler." 

If you are more ambitious, you could also make your own homemade marshmallow creme with simple ingredients — egg whites, cream of tartar, sugar, corn syrup and vanilla extract. Alternatively, you could even turn regular marshmallows into marshmallow creme yourself.

The key to making good ganache is using high-quality chocolate. But, that can be kind of a confusing term. What makes chocolate "high quality" comes down to a few different factors. For instance. it should have a higher cocoa content and not an excessive amount of sugar. It should also have a smooth texture and a glossy finish. The most important thing about high-quality chocolate is that is needs to be able to melt well. This is why you can't really use chocolate chips to make ganache, because chips have stabilizers in them that are meant to help them keep their shape when you bake them in things like cookies. 

The simplest way to find high-quality chocolate to make the whipped ganache in this recipe is to buy any kind of semi-sweet chocolate that is labeled as baking chocolate in the baking aisle of your grocery store. These bars are all meant to melt beautifully and will be perfect for this recipe.