Marshmallow Crunch Brownie Bars


I had originally planned on using the title “Marshmallow Chocolate & Peanut Butter Crunch Brownie Bars”. That seems mighty long, but is truly the best description of these bars, and they are absolutely phenomenal. Imagine this: rich, decadent brownies. Topped with ooey, gooey marshmallows. Topped again with chocolate-peanut butter-Rice Krispy deliciousness. Folks, you just can’t get much better than these bars. Part brownie, part s’more, and part Rice Krispy treat. It’s everything you know and love, baked up into one amazing dessert.


It seems insane to think that there is any way that you can improve on these bars, but I do think there is one thing I will do differently next time: I plan on cutting the quantities for the brownie layer in half. As they are, the brownie layer is about twice as thick as the marshmallow and crisp layers, and I think these would be even more awesome if all of the layers were about equal in size. I also think that taking the chocolate/peanut butter/Rice Krispy topping and using it to make an entire pan of Chocolate-Peanut Butter Rice Krispy Treats would be heavenly. Stay tuned, because that will likely be happening very, very soon. I do have more Rice Krispies left over and, well, that seems like a perfect way to use them up!

You’ll want to hurry up and make these immediately. All of your family and friends will love you forever.

More brownies with a twist:
Chipster-Topped Brownies
Cookies and Cream Cheesecake Brownies
Samoas Brownies

1 year ago: Homemade Pierogies
2 years ago: Outrageous Brownies

Marshmallow Crunch Brownie Bars

Yield: 24 bars

Prep Time: 30 minutes

Cook Time: 25 to 30 minutes

Total Time: 1 hour


For the Brownie Base:
4 ounces unsweetened chocolate
2/3 cup unsalted butter
1¼ cups semisweet chocolate chips, divided
1-1/3 cups all-purpose flour
1 teaspoon baking powder
½ teaspoon salt
4 large eggs, at room temperature
2 cups granulated sugar
2 teaspoons vanilla extract

For the Toppings:
1 bag (10½ ounces) miniature marshmallows
1½ cups milk chocolate chips
1 cup smooth peanut butter (don't use natural peanut butter)
1 Tablespoon unsalted butter
1½ cups Rice Krispies cereal


1. Preheat the oven to 350 degrees F. Grease a 9x13-inch pan.

2. For the brownies: In a medium saucepan, melt the unsweetened chocolate, butter and ¾ cup of the semisweet chocolate chips over medium heat. Stir occasionally while melting. Set aside and cool for 5 minutes.

3. In a medium bowl sift the flour, baking powder and salt. Set aside. In a large bowl , whisk the eggs thoroughly. Add the sugar and vanilla and whisk until well blended. Stir the melted ingredients into the egg mixture, mixing well. Stir in the dry sifted ingredients and mix well. Fold in the remaining ½ cup semisweet chocolate chips.

4. Pour the batter into the prepared pan, smoothing the surface with a spatula. Bake for 25 to 30 minutes, or until a cake tester inserted into the corner of of the pan comes out with moist crumbs.

5. Remove the brownies from the oven and immediately sprinkle the marshmallows over them. Return the pan to the oven for 3 more minutes.

6. Meanwhile, place the milk chocolate chips, peanut butter, and tablespoon of butter in a medium saucepan. Melt over low heat, stirring constantly, until completely melted. Remove from heat, add the Rice Krispies and mix well. Allow to cool for 3 minutes.

7. Spread the mixture evenly over the marshmallow layer. Refrigerate until chilled before cutting.

(Adapted from Culinary Concoctions by Peabody; originally from Buttercup Bakes at Home by Jennifer Appel)


143 Responses to “Marshmallow Crunch Brownie Bars”

Comment Pages 1 2 3
  1. christina on October 5, 2009 at 12:35 pm

    This is a magnificently glamorous take on rice krispie treats!


  2. Liz Brooks on October 5, 2009 at 12:38 pm

    Yum, these look great!


  3. Eliana on October 5, 2009 at 1:47 pm

    These look amazing Michelle!!!


  4. Maria on October 5, 2009 at 3:01 pm

    I can always count on you for a tasty sweet treat!


  5. Angela@spinachtiger on October 5, 2009 at 3:01 pm

    I don’t think it can get better than these.


  6. The Cooking Bride on October 5, 2009 at 3:23 pm

    Just stumbled across your blog. Those brownies look awesome. Just added you to my reader list – I look forward to following!


  7. Soma on October 5, 2009 at 4:21 pm

    I am so bad in baking…:-( The marshmallows look fabulous in the bars. if my DD saw these, she would do anything for me to make these for her:)


  8. amanda @ fake ginger on October 5, 2009 at 7:06 pm

    Those look ridiculously good! Definitely saving this recipe. I know my husband would fall in love with me all over again if I made them!


  9. Deanna@marzipan on October 5, 2009 at 7:07 pm

    These are going in my must-make-very-soon file! Looks absolutely delicious!


  10. sherri on October 5, 2009 at 7:23 pm

    I’m sold. They look scrumptious!


  11. Smartkahuna on October 5, 2009 at 7:35 pm

    ummmm, these look amazing! I just showed the picture to the Wee Kahunas and they did a happy tummy dance… :)


  12. shelly (cookies and cups) on October 5, 2009 at 7:54 pm

    ok, seriously?!?! are you trying to kill me here? these sound so good!!


  13. nicole on October 5, 2009 at 9:00 pm

    WOW! These looks AH-MAZING!!


  14. Pam on October 5, 2009 at 10:10 pm



  15. Jackie on October 6, 2009 at 12:52 am


    I was wondering could you help me with some of the measurements for the brownie layer, you recommend halving the brownie layer. For the butter would it be 5 Tablespoons of butter, if using 1/3 cup. Also for the flour, 11/3 cups, what would be the measurement for half of 11/3 cup of flour. Thank You.


  16. chocolate shavings on October 6, 2009 at 9:15 am

    The layers on those bars look amazing!


  17. stephchows on October 6, 2009 at 10:53 am

    oh wow that does sound like all the best desserts piled into one!


  18. Carla on October 6, 2009 at 12:39 pm

    I know what I’m making when I buy a box of Rice Krispies!


  19. TammyJo Eckhart, PhD on October 6, 2009 at 12:39 pm

    I agree with a few other comments that the topping could be used on a large number of goods. But since I have a soft spot in my heart for brownies, I have them in place of cake on my birthday, I really liked this combination.


  20. Jessie on October 6, 2009 at 1:38 pm

    mmmm I wish I could bake everyday and make so many wonderful treats like you do!


  21. Michelle on October 6, 2009 at 4:27 pm

    Hi Jackie – half of 1 1/3 cups of flour would be approximately 1/2 cup + 2 tablespoons flour. Or, alternately (what I would do), if you have a kitchen scale I would weight the 1 1/3 cups in grams or ounces, and then halve that amount.


  22. Mardi @eatlivetravelwrite on October 6, 2009 at 8:36 pm

    (wipes drool off keyboard as she tries to type…)



  23. Jen @ My Kitchen Addiction on October 6, 2009 at 10:31 pm

    These look incredible! Adding these to my must-bake list!


  24. Katie on October 7, 2009 at 11:16 am

    I love it! This looks so decadent and down right yummy!


  25. Stephanie on October 7, 2009 at 11:18 am

    Sounds fabulous! Great idea to make the layers even and even better to make the top layer all by itself!!


  26. COZY KITCHEN BY THE SEA on October 7, 2009 at 1:32 pm

    OOOOOOO HELLO !!!!!!!!!!!!!!!!!!!!!
    YUMMY !!


  27. Danielle on October 7, 2009 at 6:50 pm

    You sure do know how to make me smile! Yet another recipe I am dying to make!


  28. Chris on October 7, 2009 at 9:59 pm

    I’d probably like this more with more nuts and less marchmallow.


  29. Ashley on October 8, 2009 at 12:58 am

    Mmm these are one of my favourite bars!! So delicious. I don’t mind the thick brownie layer!


  30. LINA@mylifeisyummy on October 8, 2009 at 1:04 am

    wow, what a great combination. cruncy and chewy! yum!


  31. plovesp on October 8, 2009 at 1:55 am

    couldnt find marshmallows, and i had to change the quantity of ingredients and considering my low level cooking skills, it was great.. thx for the good blog beb :)


  32. Pamela on October 8, 2009 at 8:09 am

    Yum! These look delish; they’re definitely going in the bag as a “must make”! :)


  33. Tatiyana on October 8, 2009 at 3:53 pm

    Wow, these look fantastic! I know what I’m making this weekend for my family gathering. Everyone is going to love me for them being so delicious and hate me for them being so sinful! Thanks for the great post:)


  34. Dawn on October 8, 2009 at 10:26 pm

    It was the picture of these treats that had me grabbing the book “Buttercup Bakes at Home” from the store shelf! But, only after reading your blog did I have the umph to make them for the first time. Thank you! I completely agree, the brownie part is so thick – will follow your lead on the halving. Great pictures! Great Blog! :)


  35. Bonnie's Best Recipes on October 9, 2009 at 2:32 pm

    What an amazing combination of textures! Great job.


  36. Hannah on October 9, 2009 at 8:16 pm

    Wow, those look absolutely delicious.


  37. Simply Life on October 10, 2009 at 6:18 pm

    WOW. Those look AMAZING!


  38. Katrina on October 11, 2009 at 9:51 pm

    Heavenly! I recently posted some yummy very mallowy Krispy treats with caramel and chocolate. So good!


  39. Chaya on October 14, 2009 at 4:27 am

    So far, I have done very well with your recipes. This is another, I want to make.


  40. Sol on October 14, 2009 at 9:39 am

    hmmmmmmmm looks and sounds delicious so it probley is!!!!


  41. Avanika (Yumsilicious Bakes) on October 14, 2009 at 2:27 pm

    Omg these look sooo good! All the best things rolled into one! How do you come up with such stuff! I’m going to try this soon!!


  42. ashley on October 14, 2009 at 10:24 pm

    ohhh these look so delicious!


  43. Michelle on October 18, 2009 at 11:42 am

    Ohhhh… if only I had Rice Krispies in the house….

    These look WONDERFUL!!


  44. tiina on October 28, 2009 at 9:17 am

    These look perfect for a Halloween party! Thanks for sharing this great recipe!


  45. Lizzy on November 26, 2009 at 9:44 am

    These are as amazing as they sound! I made them without the marshmallow and they were still some of the most delectable treats I have ever eaten! I am making them today for the Thanksgiving crowd- they are definitely something to be thankful for!


  46. Christine on December 15, 2009 at 10:59 am

    i just made this recipe last night. While i was skeptical, this really ROCKS! It is super sweet and rich….i made a couple of changes. I used 60% bittersweet chocolate for the brownie base (decadent) and semisweet chocolate for the topping. This combo was sweet enough…i can’t imagine using semi and milk choc! The bittersweet choc adds some depth and slight complexity. Heck the brownie part alone is delicious. Thanks for sharing this recipe. This is truly a keeper.


  47. gwyn on December 17, 2009 at 10:36 am

    I made these a few days ago & finally sent the rest to work with my husband so i wouldn’t gain 10 pounds! I do think that the marshmallow was too thick & think i’d like to figure out how to double that yummy rice crispy/chocolate topping but the pan was really full as it was. Maybe by halving the brownie base i can do that. The brownie layer was so rich & so yummy – like fudge & brownie mixed together! YUM!


  48. Jacqueline on January 9, 2010 at 9:02 pm

    Wow, these are amazing! I halved the brownie layer as you suggested, and they are just sinful! I brought them into work, and my coworkers who NEVER eats anything I bring in even had one, haha! Seriously a great recipe, thank you SO MUCH for sharing!


  49. Megan on February 10, 2010 at 1:55 pm

    So awesome!! I made these and brought them into work. People said they would PAY me to bring them in again! I also had given a few to my neighbors and they were asking about them the same night! So delish!


  50. Applecore on March 5, 2010 at 5:30 am

    Wow, these are amazing! Thank you for this recipe in particular and your lovely blog in general :3 Have posted about these on my blog, Two Days Slow.


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