S’mores Upside Down Sourdough Cookies
These upside down s’mores cookies feature a fermented sourdough base with graham cracker crumble, gooey marshmallows, and chocolate chunks. The unique assembly method creates stunning marbled patterns when flipped, delivering all the nostalgic campfire flavors in a handheld treat with no sticky fingers.
Ingredients
Sourdough Cookie Base:
- 120 g active sourdough starter
- 113 g unsalted butter (softened)
- 80 g powdered sugar
- 67 g brown sugar
- 50 g egg (1 large)
- 1 teaspoon vanilla extract
- 2.5 g almond extract (optional)
- 270 g all-purpose flour
- 2 g baking powder
- 1/4 teaspoon salt
- 1/8 teaspoon cream of tartar
Graham Cracker Crumble:
- 60 g graham crackers
- 70 g all-purpose flour
- 30 g sourdough starter
- 50 g brown sugar
- 25 g powdered sugar
- 65 g cold butter (cubed)
- 5 g salt
- 7 g vanilla extract
S’mores Layer:
- 60 g mini marshmallows
- 80 g chocolate bar (chopped into chunks)
- 1 teaspoon cornstarch (for dusting marshmallows)
Instructions
- Day 1: Prepare Cookie Dough for Fermentation
- Cookie Dough
- In a large bowl, cream together softened butter, powdered sugar, and brown sugar until light and fluffy.
- Add egg, vanilla extract, and almond extract (if using), mix well.
- Add sourdough starter and mix until combined.
- In a separate bowl, whisk together flour, baking powder, salt, and cream of tartar.
- Gradually add dry ingredients to wet ingredients, mixing until just combined.
- Wrap in plastic and refrigerate for 12-24 hours.
- Crumble
- In a food processor, add flour, brown sugar, powdered sugar, and salt.
- Pulse 3-4 times to combine dry ingredients.
- Add graham crackers and pulse until you have large chunks.
- Add cold cubed butter and pulse until combined.
- Add vanilla and sourdough starter, pulse to incorporate.
- Continue pulsing until you reach a brown sugar texture that you can squeeze together and it holds its shape, but also breaks apart easily.
- Refrigerate for 12-24 hours alongside the cookie dough for fermentation.
- Day 2: Assembly and Baking
- In a small bowl, toss mini marshmallows with cornstarch to lightly coat.
- Place cornstarch-coated marshmallows in the freezer for at least 30 minutes before assembly.
- Have chocolate chunks ready for assembly.
- Preheat oven to 350°F (175°C).
- Line a large baking sheet with parchment paper.
- Using a 2.5-3 inch circle cutter as a guide, spread about 2 rounded tablespoons of graham cracker crumble mixture on the parchment in circles. For a marbled effect, leave small gaps between crumble pieces to allow marshmallow and chocolate to peek through.
- Sprinkle chocolate bar chunks evenly over each crumble circle (about 1 teaspoon per cookie).
- Embed frozen, cornstarch-coated marshmallows into the crumble (about 1 teaspoon per cookie or 4-5 mini marshmallows).
- Roll out the fermented cookie dough on a floured surface to a rough rectangle, 10″x 12″, approximately 3/8″ inch thick.
- Using your circle cutter, cut out circles from the dough.
- Gently gather scraps, press together into a ball and wrap well. Refrigerate for 15 minutes for gluten to relax before rolling again.
- When ready to assemble the next tray create another rough rectangle and continue cutting until all dough is used.
- Place each cookie circle on top of the chilled s’mores layers.
- Gently press down to adhere, making sure the graham crumble, chocolate chunks, and marshmallows are under the cookie.
- Bake for 18-22 minutes, until you can see golden browning on the graham cracker edges and cookie tops are set.
- Remove from oven and let cool completely on the baking sheet before serving.
Notes
- The 12-24 hour fermentation is crucial for developing complex sourdough flavor
- Freezing marshmallows with cornstarch coating prevents them from melting out during baking
- Leave gaps in the crumble for beautiful marbled patterns when cookies are flipped
- Store covered at room temperature for up to 2 days, refrigerate for longer storage
- Can be made with different types of chocolate bars for variety
-See the blog post for additional details
