Every Saturday morning I open the fridge, see the jar of sourdough discard, and feel that little pang of waste. This Saturday it finally got to stay. My husband saw me pulling it out and said the quiet part loud: make the s’mores cookies again. So I did. By the time the second batch came out of the oven, we’d eaten half of them, and I already knew there’d be leftovers. There weren’t.
These cookies have the same soft, chewy texture as a good chocolate chip cookie, with crushed graham crackers and marshmallows folded in. In the oven, the marshmallows caramelize — crunchy around the edges, gooey in the middle. It tastes exactly like a summer campfire, minus the mosquito bites.
What you’re getting, and what it takes
Real time: about 15 minutes of hands-on work, plus chilling the dough. Bake time: 10 to 12 minutes for regular-sized cookies, 18 to 20 minutes for the big bakery-style ones I like to make. Yields 24 cookies.
The only commitment is the chill time. Refrigerate the dough for at least 2 hours before baking. I’m usually not patient, but trust me — it’s worth it. If you have the time, refrigerate for up to 3 days. The flavor gets even better.
Ingredients
- 1 cup unsalted butter, softened
- 1 cup white sugar
- ¾ cup brown sugar
- ½ cup sourdough starter discard (active starter works too)
- 2 teaspoons vanilla extract
- 1 large egg
- 2 ½ cups all-purpose flour
- 2 teaspoons cornstarch
- 1 teaspoon baking soda
- ½ teaspoon baking powder
- 1 teaspoon salt — don’t skip this, it makes the difference
- 2 cups chocolate chips (a 12 oz bag)
- 2 cups marshmallows
- 1 cup graham crackers, crushed
Two honest notes. Both sugars together are what give the dough its chew, so don’t swap one out for the other. And if you’re using discard straight from the fridge, no need to warm it up — cold works perfectly.
How to make them
- Cream the softened butter, white sugar, and brown sugar in a stand mixer (or with a hand mixer) until light and fluffy.
- Add the egg, vanilla, and sourdough discard. Mix until fully combined, scraping down the bowl as you go.
- In a separate bowl, whisk together the flour, cornstarch, baking soda, baking powder, and salt.
- With the mixer on low, add the dry ingredients in batches until a dough forms. Stop mixing the moment it comes together — overmixing makes for tough cookies.
- Fold in the chocolate chips, crushed graham crackers, and marshmallows.
- Cover the dough and refrigerate for at least 2 hours, or up to 3 days for deeper flavor.
- Preheat the oven to 350°F. Line a baking sheet with parchment paper.
- Scoop the dough onto the sheet. I go big — about 70 grams per cookie, roughly two scoops each — but regular-sized scoops work fine too.
- Bake 10 to 12 minutes for regular cookies, or 18 to 20 minutes for the bakery-size ones, until the edges just start turning golden. They keep setting as they cool, so don’t overbake.
- Let them cool on the baking sheet for a few minutes before moving them to a wire rack.
Storage
Kept in an airtight container at room temperature, the cookies stay good for up to 4 days. For longer, freeze the baked cookies for up to 3 months — or freeze the dough balls and bake fresh whenever the craving hits. That’s the part I live for: pulling a handful of dough from the freezer on a random Tuesday and having cookies by the time the kettle boils.
Questions I actually get asked
Can I use cold discard straight from the fridge? Yes, it works perfectly.
Can I long-ferment the dough? Absolutely — up to 3 days in the fridge before baking.
Why did some of my marshmallows disappear? Some of them melt into the dough while baking. That’s normal, and it’s what gives you the little caramelized bits throughout the cookie.
Can I use mini marshmallows? Yes, and they distribute more evenly.
Can I make these ahead? The dough holds in the fridge for several days, and dough balls freeze for up to 3 months.
Make it yours
Reserve a few extra chocolate chips and marshmallows and press them into the tops before baking — that’s what gives them the bakery-style look. Swap in white chocolate chips and you’ve got a s’mores take that leans sweeter. And if your crumbler crackers are running low, a handful of crushed vanilla wafers work in a pinch, though you lose the classic flavor.
Happy cooking, Maya