No-Bake Peanut Butter Marshmallow Cereal Bars


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These bars are a hybrid of some of my favorite bars.

No-bake, ChewyGooey, Caramely, with Peanut Butter, Special K, Cereal, Marshmallows.

No-Bake Peanut Butter Marshmallow Cereal Bars - Easy 5-Minute Recipe at

And they’re so good. And so easy.

Ever since I made the Chewy Peanut Butter and Chocolate Cereal Bars, I’ve been thinking about how to remake them in a slightly new way.

No-Bake Peanut Butter Marshmallow Cereal Bars - Easy 5-Minute Recipe at

These bars are based heavily on those, but instead of using Rice Krispies, I used Special K. You could also use Corn Flakes, Frosted Flakes, Rice Krispies, or a similar vegan or gluten-free cereal.

Instead of topping them with chocolate-peanut butter swirls, I stirred in marshmallows. I love marshmallows in bars because they lend so much gooey-and-chewy texture.

Plus, marshmallows are more well-behaved in the Caribbean heat and don’t melt everywhere like chocolate.

No-Bake Peanut Butter Marshmallow Cereal Bars - Easy 5-Minute Recipe at

No-bake bars like these are always nice so you don’t have to heat up your house, especially this time of year.

And they’re made in one bowl in the microwave, and take less than 5 minutes to stir together. Usually it’s the fast and easy recipes people seem to make anyway, and you can add this one to the Fast and Easy list.

No-Bake Peanut Butter Marshmallow Cereal Bars - Easy 5-Minute Recipe at

There’s no butter in the recipe, but you’d never guess it because they’re exceedingly buttery-tasting and rich.

The microwave-made sauce drenches the cereal in a sweet, brown sugary, caramel-vanilla, peanut buttery syrup and holds the bars together.

No-Bake Peanut Butter Marshmallow Cereal Bars - Easy 5-Minute Recipe at

I love bars that I can really sink my teeth into, and these deliver.

They’re dense, wonderfully soft, with tons of chewiness and texture from the cereal and marshmallows.

No-Bake Peanut Butter Marshmallow Cereal Bars - Easy 5-Minute Recipe at

Peanut butter has a way of making everything taste so good and decadent.

Even Special K.

No-Bake Peanut Butter Marshmallow Cereal Bars - Easy 5-Minute Recipe at

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Yield: one 8-by-8-inch pan, 9 to 12 squares

No-Bake Peanut Butter Marshmallow Cereal Bars

No-Bake Peanut Butter Marshmallow Cereal Bars

These fast, easy, no-bake bars are a hybrid of some of my favorite bars, which include peanut butter, marshmallows, cereal and are held together with a brown sugar-caramel sauce that’s made in the micro in 1 bowl. They’re dense, wonderfully soft, with plenty of chewiness and texture and you can really sink your teeth into them. There’s no butter in the recipe, but you won’t miss it because the bars are rich and very buttery tasting.

Prep Time 5 minutes
Cook Time 2 minutes
Additional Time 1 hour 53 minutes
Total Time 2 hours


  • 1 heaping cup creamy peanut butter (use Jif, Skippy, or similar; do not use natural or homemade peanut butter)
  • 1/2 cup light corn syrup (light colored, not lite)
  • 1/2 cup granulated sugar
  • 1/4 cup light brown sugar, packed
  • 1 tablespoon vanilla extract
  • 3 1/2 cups Special K cereal (Corn Flakes may be subsituted, or use about 3 cups Rice Krispies cereal)
  • about 5 ounces marshmallows (half of one standard bag; I used large but mini are ideal)


  1. Line an 8-inch square pan with aluminum foil leaving overhang, spray with cooking spray; set aside.
  2. In a large microwave-safe bowl, combine 1 heaping cup peanut butter, corn syrup, sugars, and heat on high power for 1 minute to melt.
  3. Stop to stir. Mixture will be on the granular side, this is okay.
  4. Return bowl to microwave and heat for 1 more minute on high power.
  5. Stir in the vanilla.
  6. Stir in the cereal and marshmallows. The marshmallows will melt to some extent, but not fully.
  7. Turn mixture out into prepared pan, packing it down somewhat firmly with a spatula, and smooth the top.
  8. Cover pan with a sheet of foil (to prevent fridge smells), and place pan in fridge to set up for about 2 hours or until set, before lifting out with foil overhang, slicing, and serving.
  9. Bars will keep airtight at room temperature for up to 1 week, in the refrigerator for up to 2 weeks, or in the freezer for up to 6 months.

Adapted from Chewy Peanut Butter and Chocolate Cereal Bars

Nutrition Information:



Serving Size:


Amount Per Serving: Calories: 288Total Fat: 11gSaturated Fat: 2gTrans Fat: 0gUnsaturated Fat: 7gCholesterol: 0mgSodium: 182mgCarbohydrates: 45gFiber: 1gSugar: 32gProtein: 7g

Related Recipes:

Chewy Peanut Butter and Chocolate Cereal Bars (no-bake, vegan, GF)

Chewy Peanut Butter and Chocolate Cereal Bars (vegan, gluten-free) - Recipe at

Peanut Chewy Payday Bars (almost no-bake)

Peanut Chewy Payday Bars

Caramel and Chocolate Gooey Bars

Caramel and Chocolate Gooey Bars

Double Chocolate Caramel Corn & Cocoa Rice Krispies Candy Bars

Double Chocolate Caramel Corn & Cocoa Rice Krispies Candy Bars

Nutella and Peanut Butter Graham Bars with Chocolate Frosting

Nutella and Peanut Butter Graham Bars with Chocolate Frosting

Browned Butter Rice Krispies Treats – The best RKTs I have ever had. Double the butter and it’s browned, for great flavor and soft, buttery, chewy bars

Browned Butter Rice Krispies Treats

Special K Bars

Special K Bars
Underside of Special K Bar

No-Bake Nutter Butter Special K Bars

No-Bake Nutter Butter Special K Bars

Peanut Butter Caramel Twix Bars (almost no-bake)

Peanut Butter Caramel Twix Bars

Peanut Butter Chocolate Chunk Cookie Bars

Nutella-Swirled Peanut Butter Chip Blondies

Nutella-Swirled Peanut Butter Chip Blondies - Easy One-Bowl No-Mixer Recipe at

Biscoff Marshmallow Chocolate Bars

Biscoff Marshmallow Chocolate Bars from

Marshmallow Caramel Oreo Cookie S’Mores Bars

Marshmallow Caramel Oreo Cookie S’Mores Bars

 Thanks for the entries in the 3-Piece Baking Set and Gluten-Free Dough Giveaway and the $100 My Sweet Muffin Giveaway

What’s your favorite no-bake or fast and easy dessert?

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Welcome to AverieCooks! Here you’ll find fast and easy recipes that taste amazing and are geared for real life. Nothing fussy or complicated, just awesome tasting dishes everyone loves!

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    1. I haven’t tried to so I cannot say for sure. I am doubtful honey, agave, maple syrup would work but you can try and see.

  1. These look great! I love bars made with cereal – it always adds that crunch that I love so much. I do have a question, though. Out of curiosity, what happens if you use natural or homemade peanut butter?

    Can’t wait to try these!!!

  2. I need some help, in France we don’t have your “corn syrup”, so what can I put in the receipe instead of it? thx

    1. Possibly golden syrup or honey? I don’t know because I haven’t tried them if they will work exactly, but it would be a good start.

      1. done! it’s such… hmmmmmmmmmm! i tried the peanut butter bar with chocolate and cereal, really easy, fast and so good! thx for these ideas!

  3. Just what I’m looking for. I’m stuck with no oven for a while and I’m so glad I came across these beauties. Stopping by from Tuesday Talent Show!

    1. Oh thanks for clicking over and yes, no bake bars to the rescue (especially this time of year!) There are lots of related recipe links in the post too that are no-bake bars and goodies!

  4. You always have such an interesting ideas for cookies and bars. Mushmellows in this one must taste great.

  5. Omigosh, do I love these! They honestly sound like the food equivalent of a big, fat hug. I mean cereal, marshmallows and peanut butter? I can’t think of a more comforting combination. Top it off with ‘no-bake’ and this is like hours of hugging it out. Perfect for lazy, hot, late summer days, Averie!

    1. “the food equivalent of a big, fat hug” = YES, so true! Perfect way to say it! They are indeed!

  6. It’s hard to beat really easy cereal bars like this – especially when PB is involved!

  7. The world needs more no bake recipes in the month of August. :) These look amazingly chewy, Averie! I’m loving the addition of marshmallows. Like sprinkles, I think marshmallows can do no wrong. :)

  8. FAB! I loved that you used Special K-and just wonderful pb marshmallowy goodness. Hooray!

  9. I love how chewy, ooey, and gooey these looks! I haven’t baked with marshmallows in a while but I do have some in the cupboard… Hmmmm. Making these bars may just have to go on the to-do list this week. ;)

  10. I LOVE, LOVE, LOVE peanut butter. I generally don’t buy it simply because I have no self control when it comes to the stuff. But I might have to make an exception and get some PB so I can try these bars. I especially like that they are no-bake so I don’ t have to heat up my kitchen on a hot summer’s day. Thanks for the inspiration!

  11. Yes love this. I would never have thought of this. Might try them with Rice Krispies. Thanks for a great recipe :)

  12. Mmm! I can almost taste the gooey sweetness of these bars! I need to make bars like this more often. I forget how good they are! (And how versatile other cereal is, besides rice krispies!)

  13. I can’t believe there’s no butter in these…I would never have guessed! I love how ooey gooey they are! These could be dangerous around the house… but that’s just how I live– on the edge of danger… with lots of sugar!

  14. Averie I am loving these! I am all about no-baking lately because quite frankly – I don’t want to turn on my oven! When we were at the lake, there were SO many of us that I just decided to make no-bake pies instead of cake for Kevin’s birthday. The house was already so hot from everyone inside it! Anyway, these bars are just glorious. I love marshmallow and PB together. These look like a texture lovers dream!

    1. Nobake pies sound great. You are the queen of all those anyway with so many on your site I’ve always wanted to try! And PB + brown sugar (which turns to caramel in the micro) + m’mallows is so good. And they ARE indeed a texture lover’s dream!

  15. Some of my best creations come from experimenting with my old “hybrid” recipes.
    So, yeah, keep going. LOL

    1. As bloggers we have to keep things fresh but I tell you, if I didn’t blog, there are certain desserts I’d make over and over and over and never change one thing to them :)

  16. These look great and I love how versatile they can be just by mixing up the type of cereal you use! Yum!

  17. Ahhh Averie! I love that you combined 3 of my favorite things- peanut butter, marshmallows and convenience! Lol ;) I’m in love with no-bake bars and they’re especially good when they’re dense and chewy like these. I’ve been wanting to experiment with no-bake bars lately….just haven’t gotten around with it. I’m thinking something with oats/oat flour and almond butter as the main components. Maybe a little coconut oil too ;) I’ll let you know if I get a chance to make these! Happy Sunday!

  18. So mouth watering, Averie! I love how you take those extra steps like cutting squares of parchment paper for each bar :)
    Lately I’ve been making an easy dessert in the food processor of banana ice cream with frozen banana, peanut butter, bits of chopped TJ’s dark chocolate, and some vanilla extract.

    1. I do it b/c it looks nice but really, b/c things melt here in the heat and I don’t want the gooey stuff melting and sticking to my wood table. In San Diego it’s not an issue but here in Aruba, hot, humid, sticky city :) But thanks for noticing (b/c it’s a total pain and does take time! lol) Your easy dessert sounds wonderful!

  19. I love how much you love peanut butter. And no bake – even better! Thanks for these!

  20. Since these bars are made with Special K that means they’re healthy, right? So it’s okay to enjoy several… :D

    I love your hybrid creations!

  21. You had me at “peanut butter”, “marshmallow” and “no bake”. In other words, the entire thing! Delicious!

  22. Oh goodness! I have all of the ingredients to make these right now. These are going to be pretty dangerous to have around, but I’m betting they’re totally worth it! thank you for sharing :)

  23. I love this spin on the special K-Bar!! Special K- BArs are my family favorite and these look like they could compete! WOW oh wow! I love all that gooeyness on top and the peanut butter. YUM!!

    1. I know you have a recipe for them, too! My Special K bar recipe is from 2010 so I figured it could use a little updating. Then again, it was my grandma’s recipe from like 1960 and has served us very well :)

  24. Cereal bars like this are the best! I’m so happy you made these – they sound delicious!

  25. Something very similar to these is actually on the menu for this morning. I love peanut butter no bake treats like this and adding marshmallows was a great idea!

  26. Gawd, I love reading the phrase “do not use natural or homemade peanut butter.”

    Almost as much as “does not contain raisins.”

    1. There are times for natural PB and then there are times for Jif, Skippy, or Peter Pan. They are like glue and work WONDERS here whereas natural is like a soft oil slick and not really ideal :)

  27. I love a gooey bar–and no bake cereal bars and cheesecake taste good any time of year, but especially in the summer. My most frequently made fast summer dessert is throwing frozen stuff into the vita for instant sorbets or ice cream. Hmmm….I think a little coconut milk ice cream or banana soft serve might be good on top of these too!

    1. Funny I am just getting ready to make a version of banana softserve. I haven’t quite decided what’s going into the blender yet though!

  28. I love bar like this. They are honestly the one thing I eat by my self because I am too ashamed to admit I still love them at 21… Eh.. more for me.
    PB and marshmallow? Heaven in a portable snack!

  29. These look so amazing! I love that you added the marshmallows. That totally takes these into over-the-top awesomeness! :)