Tessa’s Recipe Rundown
Taste: Signature s’mores flavors with the addition of bold peanut butter and butterscotch flavors.
Texture: Chewy, soft blondie layers with gooey marshmallow and slight crunchiness from the chocolate chips.
Ease: So easy!
Why You’ll Love This Recipe: Fabulous twist on s’mores that’s easy to transport and serve.
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One bite of these Peanut Butter S’mores Blondies will transport you to a cozy campfire.
These thick, chewy blondies are packed with rich peanut butter flavor and a hint of butterscotch (thanks to the brown sugar!), with graham cracker crumbs folded right into the dough.
Layer that heavenly mix with gooey marshmallow fluff and perfectly melty chocolate, and you’ve got the ultimate nostalgic treat.
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I love reinventing classic s’mores flavors into easy-to-serve desserts – like my delicious S’mores Fudge Bars, easy S’mores Cookies, and no-bake S’mores Mini Cheesecakes.
This time, I couldn’t resist adding peanut butter to the mix. It’s seriously dessert heaven!
These Peanut Butter S’mores Blondies are sure to be a hit with any s’mores or peanut butter lover in your life.
Sprinkle of Science
How to Make Peanut Butter S’mores Blondies
The Peanut Butter
- I recommend using natural peanut butter for the best bold peanut butter flavor. My favorite is Kirkland Organic (from Costco).
- Make sure it’s very well stirred and completely smooth, with no oily or dry bits.
- Conventional peanut butter (Skippy, Jif, etc.) should work just fine, but it’ll be sweeter with a weaker flavor.
- I conducted a side-by-side experiment using conventional vs. natural peanut butter in baking – check out the peanut butter experiment here.
Can I Use Almond Butter Instead?
While we haven’t tried that here, that swap works perfectly in my Peanut Butter Cookies! So feel free to experiment with using the same amount of almond butter in place of the peanut butter. Let me know how it turns out!
The Marshmallow
Any brand of marshmallow creme or fluff should work just fine.
Use a rubber spatula or a small offset spatula to spread the marshmallow fluff across the bottom layer of peanut butter blondie dough. It doesn’t have to be perfect!
If this is too challenging, cover the blondie dough and pop it in the freezer for 15 minutes to firm it up slightly before spreading the fluff.
The Chocolate
I prefer semisweet chocolate chips (Ghirardelli brand) for the best flavor and balance of sweetness. You can substitute the same amount by weight of chopped baking chocolate, chocolate chunks, or mini chocolate chips if you prefer.
The Graham Crackers
Pre-made graham cracker crumbs are the easiest option. If you only have whole graham crackers, pulse 4 full cracker rectangles in a food processor until finely ground, then measure out 1/2 cup or 57 grams. Alternatively, place the crackers in a ziptop bag and crush with a rolling pin or mallet until finely ground.
The Extra Egg Yolk
Don’t skip the additional egg yolk! The added fat from this extra yolk helps create moist and perfectly chewy bars. If you skip this extra yolk, your blondies will be softer, less chewy, and could be a little dry.
The Best Pan for Peanut Butter S’mores Blondies
- I love this 8 by 8-inch metal pan for all blondies, brownies, bar cookies, and more!
- Be sure to use a pan at least 2 inches deep, like the one above, as these blondies are pretty thick.
- I don’t recommend using glass, ceramic, or silicone pans for this recipe because they don’t conduct heat as efficiently.
- Learn more about Glass vs. Metal Pans here.
- Line your pan with foil or parchment paper, leaving an overhang, and spray with nonstick cooking spray, to prevent any marshmallow mess.
Can I Double This Recipe?
Sure! Use a 9 by 13-inch pan and simply double all ingredients. Add a couple minutes to the bake time if needed (see note just below about overbaking).
Important: Do Not Overbake Blondies
Sensory indicators are important here, as these are thick bars and ovens will vary in bake times. Look for the edges to be a light golden brown, with some slight golden browning on the puffed marshmallow filling peeking out. The center should still have a slight jiggle. Be careful not to overbake, as this can lead to dry blondies.
How to Slice Blondies
For perfect slices, allow the blondies to cool completely. Use a sharp knife and run it under hot water, carefully wiping it dry between each cut.
How to Store Peanut Butter S’mores Blondies?
These Blondies will keep in an airtight container at room temperature for 3 days or in the fridge for 4 days.
Can You Freeze PB S’mores Blondies?
Peanut Butter S’mores Blondies freeze and thaw very well! Be sure to wrap slices individually in plastic wrap and place inside an airtight container to prevent them from drying out. Freeze for up to one month. Allow to sit at room temperature to thaw before serving.
More Recipes You’ll Love:
- S’mores Fudge Bars (Joe says these are a “hall of fame” dessert!)
- S’mores Pizookies
- Peanut Butter & Jelly Cookies
- Cookie Butter Brownie Ice Cream Sandwiches
- Peanut Butter Pie
Peanut Butter S’mores Blondies
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Ingredients
- 6 tablespoons (85 grams) unsalted butter
- 3/4 cup plus 2 tablespoons (175 grams) brown sugar, preferably dark brown1
- 1/2 cup (135 grams) creamy natural peanut butter, very well stirred2
- 1 cup (127g) all-purpose flour
- ½ cup (57g) graham cracker crumbs3
- 1/4 teaspoon baking powder
- 1/8 teaspoon baking soda
- 1/4 teaspoon fine sea salt
- 1 large egg + 1 egg yolk4, at room temperature
- 1 1/2 teaspoons vanilla extract
- 1 cup (104 grams) marshmallow creme
- 1 cup (170 grams) semisweet chocolate chips
Instructions
- Preheat the oven to 350°F. Line an 8 by 8-inch light-colored metal pan5 with parchment or foil, leaving an overhang on all sides, then spray with nonstick baking spray.
- In a large microwave-safe bowl, melt the butter. Add the brown sugar and peanut butter, stirring until smooth. Set aside to cool.
- In a medium mixing bowl, combine the flour, graham cracker crumbs, baking powder, baking soda, and salt. Set aside.
- Whisk the egg and egg yolk into the cooled peanut butter mixture, one at a time, whisking well after each addition. Add the vanilla extract and stir to combine. Add the flour mixture and stir until just combined. Dough will be fairly thick.
- Press two-thirds of the dough into the prepared pan, spreading evenly to the edges of the pan. Use a spatula to dollop the marshmallow creme around the base layer, then smooth as evenly as possible over the dough. It will be messy, don’t worry about making it perfect. Sprinkle the chocolate chips evenly over the marshmallow.
- Using your hands, pick up portions of the remaining dough and flatten with your palms. Top the marshmallow and chocolate chips with pieces of the flattened dough to cover about two-thirds of the top.
- Bake for about 26-28 minutes or until the center is slightly jiggly, the edges are lightly golden brown, and the marshmallow on top is puffed and lightly golden brown. Be careful not to overbake to avoid dry blondies. Allow to cool in the pan completely. Cut into squares and serve.
- Store leftovers in an airtight container for up to 3 days.
Recipe Notes
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This recipe was originally published in 2014 and has been updated with recipe improvements, additional baking tips, and new photos. Photos by Joanie Simon.
I sooo wanna make these but don’t have Hershey bars! Only have morsels… how can I substitute to make this deliciousness NOW!?!?!
The recipe says to grease the pan but the pictures show a foil-lined pan. Do you line with foil, then grease the foil?
Yes! Just corrected the recipe instructions 🙂
Do you refrigerate the leftovers? Just made them and they are fabulous!!
I just stored them in an airtight container at room temp!
Baked these the other night for a friends bday… Everyone LOVED them!! I did have to bake them about 10 extra mins and was still concerned they were not cooked all the way through but they were gone so fast, no one seemed to mind. Def gonna make these again!!!
Yay! So thrilled to hear that 🙂
I’m loving every layer of these delicious bars!
Thanks so much Jamie!
Totally irresistible! I want these now!
These sounds SO GOOD! So exactly my kinda treat.
The Peanut Butter S’Mores Blondies recipe is a bit unclear. I believe the eggs and vanilla are supposed to be added to the sugar/peanut butter mixture. Then, that mixture is stirred into the dry ingredients.
Just put them in the oven–can’t wait to try them!
These are mouthwatering. I hope there’s a Youtube video coming out!
These looks yummy, I’ve got to try this Pinned!
These look to-die-for! I just love when a recipe works out well and you get a great reaction from your taste testers 🙂
I just about died seeing your email in my inbox this morning – these have got to be the prettiest and most decadent looking s’mores bars ever!! Love that there is peanut butter and a Blondie base – can’t wait to try these! Pinned 🙂