Indulge in these soft and chewy s’mores cookie bars, a delightful twist on a classic treat.
Made with fiber-rich whole wheat flour, wholesome peanut butter, and gooey marshmallows, they provide a balance of plant-based protein and healthy fats.
Quick to prepare and perfect for any occasion, these bars make a satisfying, crowd-pleasing snack or dessert that’s ideal for everyday enjoyment.
Peanut Butter and Chocolate S’mores Bars
Equipment
- 8×8-inch square baking pan – 1
- Parchment paper – enough to line pan with 2-inch overhang
- Binder clips (¾-inch) – 2
- Large mixing bowl (1)
- Handheld mixer or rubber spatula – 1
- Offset spatula (optional) – 1
- Microwave-safe bowl – 1
- Knife, lightly oiled – 1
Ingredients
- 6 tbsp 84g unsalted butter, softened
- ½ cup + 1 tbsp 125g light brown sugar, packed
- 1 large egg room temperature
- 1 tbsp 15ml honey
- 1 tsp 5ml pure vanilla extract
- 1 cup 142g all-purpose flour
- ½ cup 71g whole wheat flour
- ½ tsp salt
- ¼ tsp baking powder
- ¼ tsp ground cinnamon
- ⅛ tsp baking soda
- 2 x 100g milk chocolate bars or 200g chips
- ½ cup 120g smooth or crunchy peanut butter
- 21 regular-sized marshmallows
Instructions
- Prepare Your Baking Pan: Start by preheating your oven to 350°F (175°C). Take an 8×8-inch square metal baking pan and line it with parchment paper. Make sure to leave a 2-inch overhang on opposite sides; this will help you lift the bars out easily after baking. To keep the parchment in place, use ¾-inch binder clips on the edges. This ensures your layers stay neat and your pan remains clean.
- Cream the Butter and Sugar: In a large mixing bowl, combine softened butter, light brown sugar, and honey. Using a handheld mixer or a wide rubber spatula, beat or stir the mixture until smooth and slightly fluffy. This step is crucial because properly creamed butter and sugar create a light texture in your cookie bars. Make sure there are no lumps, and the mixture looks creamy and uniform.
- Add the Egg and Vanilla: Once the butter and sugar mixture is creamy, add 1 large egg and 1 teaspoon of vanilla extract. Mix thoroughly until fully combined. Scrape down the sides of the bowl to ensure the egg is evenly incorporated. The egg adds moisture and helps bind the dough together, while vanilla provides depth of flavor.
- Incorporate the Dry Ingredients: In a separate small bowl, whisk together all-purpose flour, whole wheat flour, salt, baking powder, baking soda, and ground cinnamon. Gradually sprinkle this dry mixture into your wet ingredients. Fold carefully using a spatula until just combined. Be gentle to avoid overmixing, which could make the cookie bars tough. The dough should be soft and slightly sticky, yet manageable.
- Form the Base Layer: Take two-thirds of the dough and press it evenly into the bottom of your prepared pan. Use floured hands or a small offset spatula to smooth it out. This base will serve as the foundation for your s’mores layers, so make it even and consistent in thickness. Don’t worry if the dough is sticky—lightly flouring your hands prevents it from sticking too much.
- Layer the Chocolate: Place your milk chocolate bars over the dough. Arrange them so that they cover the entire surface, pressing lightly to create an even layer. If using chocolate chips, sprinkle them evenly across the base. This chocolate layer will melt slightly during baking, adding a rich, gooey sweetness to every bite.
- Add the Peanut Butter: Melt ½ cup peanut butter in a microwave-safe bowl for about 30 seconds, just enough to make it pourable but not runny. Drizzle the melted peanut butter evenly over the chocolate layer. This creates a creamy, nutty layer that complements the chocolate and marshmallows perfectly.
- Top with Marshmallows: Scatter 21 regular-sized marshmallows over the chocolate and peanut butter. Place the pan in the oven for 3 minutes to gently melt the marshmallows. Then, switch to the broiler setting and toast for about 1 minute—keep a close eye on them to avoid burning. Once golden and puffy, immediately press them down slightly with an oiled offset spatula. Try to spread them evenly while still sticky; this will help the top layer of dough adhere better.
- Cover with Remaining Dough: Divide the remaining one-third of the dough into four portions. Roll or pat each portion into flat sheets using as much flour as needed to prevent sticking. Drape each sheet over the marshmallow layer, covering as much as possible.It’s perfectly fine if marshmallows peek through—this adds a rustic, appealing look. Gently press the dough edges to seal slightly.
- Bake Until Golden: Place the pan in the preheated oven and bake for 20–25 minutes, or until the top is a beautiful golden brown. The bars should be set but still soft and chewy. Baking time may vary slightly depending on your oven, so start checking around 18 minutes.
- Cool Before Slicing: Allow the s’mores bars to cool for at least 1 hour. This helps the marshmallow layer stabilize and makes slicing easier. For the cleanest slices and least mess, let the bars cool for 8 hours or overnight. When ready to cut, lightly oil a sharp knife and wipe it clean between each slice to prevent sticking.
- Serve and Enjoy: Once sliced, serve your s’mores cookie bars warm for gooey indulgence, or enjoy them cold for a more set texture.These bars are perfect as a dessert, snack, or even a portable treat for gatherings. Store leftovers in an airtight container at room temperature for up to 3 days, or refrigerate for up to 5 days for longer freshness.
Notes
- For best results, use room-temperature butter and egg to ensure smooth, evenly mixed dough.
- If dough sticks to your hands, lightly flour your palms or use an offset spatula.
- Toast marshmallows carefully under the broiler and watch closely to prevent burning.
- For a neater look, allow bars to cool completely before slicing; overnight chilling is ideal.
- Chocolate can be substituted with chocolate chips, chunks, or dark chocolate depending on preference.
- This recipe works well with crunchy or smooth peanut butter for different textures.
- Bars can be cut into different sizes for portion control or serving flexibility.
Chef’s Secrets for Perfect Bars
The key to perfect s’mores cookie bars lies in balancing texture and flavor.
Using a combination of all-purpose and whole wheat flour gives the bars a slightly nutty flavor and a chewy, yet tender bite.
When pressing the base dough into the pan, flour your hands lightly to prevent sticking but avoid overworking the dough, which can make it tough.
Toasting the marshmallows under the broiler is crucial—just a minute can create a golden, caramelized top that enhances both flavor and appearance.
Finally, let the bars rest long enough before slicing; this allows the layers to set properly, keeping each square intact and gooey but not messy.
Serving Suggestions to Impress Everyone
These s’mores bars are versatile and perfect for any occasion.
Serve them warm with a scoop of vanilla ice cream for a decadent dessert or pair with a glass of cold milk for a comforting snack.
They also work well as a portable treat for picnics, lunchboxes, or coffee breaks.
For a fun twist, drizzle extra melted chocolate or a sprinkle of crushed graham crackers on top before serving.
Even a dollop of whipped cream or a few fresh berries can elevate the presentation for special occasions.
Storage Tips for Freshness
To maintain the bars’ soft and chewy texture, store them in an airtight container at room temperature for up to 3 days.
If you prefer firmer, sliceable bars, refrigerate them for up to 5 days—just allow them to come to room temperature before serving for the best flavor.
For longer storage, these bars can be frozen for up to 2 months.
Wrap tightly in parchment or plastic wrap and place in a freezer-safe container.
When ready to enjoy, thaw overnight in the fridge or warm gently in the oven for that fresh-out-of-the-oven experience.
Frequently Asked Questions
1. Can I make these bars gluten-free?
Yes! Substitute the all-purpose and whole wheat flour with a gluten-free baking blend.
The texture may be slightly different—slightly more crumbly—but the flavor remains rich and delicious.
Make sure your chocolate and marshmallows are also certified gluten-free.
2. Can I use crunchy peanut butter instead of smooth?
Absolutely! Crunchy peanut butter adds texture and an extra nutty bite to the bars.
Melt it slightly before drizzling to make it easier to spread evenly over the chocolate layer.
3. How do I prevent marshmallows from sticking?
Use an oiled offset spatula or buttered knife to press and spread the marshmallows.
Allowing the bars to cool completely also reduces stickiness. Cleaning your knife between slices keeps each cut neat.
4. Can I prepare these bars ahead of time?
Yes! You can assemble the layers ahead and store the unbaked pan in the refrigerator for up to 24 hours before baking.
Baking fresh gives the best texture, but this is handy for meal prep or parties.
5. Can I substitute chocolate types or flavors?
Definitely! Dark, semi-sweet, or even white chocolate bars work well.
For a more decadent twist, add chocolate chunks, Nutella, or flavored chocolate spreads.
Adjust the sweetness slightly depending on your chocolate choice.
