Triple Peanut Butter Monster Cookie Bars – Soft, gooey bars loaded with M&Ms, chocolate and made for serious peanut butter lovers! So good!
I make my fair share of treats, and have the hodgepodge of random add-ins in my pantry to show for it.
Half-used bags of chocolate chips, peanut butter chips, and a random assortment of candy were taking over the cupboard so I found a home for them.
In these bars.
They’re the perfect bar to toss in everything but the kitchen sink.
Use this flexible and forgiving dough base as your opportunity to stir almost anything that’s plaguing your pantry into it.
What else are you going to do with 1/3 cup chocolate-covered sunflower seeds from your last Trader Joe’s impulse buy or that small handful of butterscotch chips from your last batch of cookies, or a few stray marshmallows.
Use up last year’s Halloween candy or Easter candy. Those Fun-Size Twix bars are begging to be diced and tossed in. Don’t pretend you don’t discover random candy from months ago. Well, I do. Life of a food blogger.
The bars come together in 5 minutes in one bowl, no mixer needed. Unlike making cookies, there’s no dough to chill, and they’re ready in under 30 minutes from start to finish.
I used my go-to blondie base, with a half-cup peanut butter stirred in, before stirring in the kitchen sink.
I had partially used bags of Peanut Butter M&M’s, peanut butter chips, chocolate chips, chocolate chunks, toffee bits, and included them all.
Because peanut butter is used three times – peanut butter that’s stirred into the dough, Peanut Butter M&Ms, and peanut butter chips – they pack a bold, peanut buttery punch.
They’re very moist and soft. The edges turn slightly chewy, while the interior remains a squishy, soft heaven.
The crunchy candy coating of the M&Ms and their firmness, coupled with Heath toffee bits, are the perfect texture contrast to the buttery, peanut buttery, dense, melt-in-your mouth dough.
There’s plenty of chocolate, too. Chocolate and peanut butter just go together. The abundance of melted chocolate chips is practically mandatory with all that peanut butter.
Soft, chewy, fast, easy, peanut butter used three times, and you can clean out your cupboards. That’s success.
And let’s face it, any time you can bake candy into a dessert, you won’t hear too many complaints.
Cleaning out your pantry never tasted so good.
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Triple Peanut Butter Monster Cookie Bars
Ingredients
- ½ cup unsalted butter, 1 stick, melted
- 1 large egg
- 1 cup light brown sugar, packed
- 1 tablespoon vanilla extract
- heaping 1/2 cup creamy peanut butter, use Jif, Skippy, etc.; don’t use homemade or natural – too runny
- 1 cup all-purpose flour
- 1 cup Peanut Butter M&Ms
- ¾ cup semi-sweet chocolate chips or chunks, or a combination
- ½ cup Reese’s Peanut Butter Chips
- ⅓ cup Heath Bar Toffee Bits
Instructions
- Preheat oven to 350F. Line an 8-by-8-inch baking pan with aluminum foil, spray with cooking spray; set aside.
- In a large, microwave-safe bowl melt the butter, about 1 minute on high power.
- Wait momentarily before adding the egg so you don’t scramble it. Add the egg, brown sugar, vanilla, and whisk until smooth.
- Add the peanut butter and whisk or stir until smooth and incorporated.
- Add the flour and stir until just combined, don’t overmix.
- Add all remaining add-ins and fold to incorporate.
- Turn batter out into prepared pan, smoothing the top lightly with a spatula. I like to strategically place a few M&Ms on the top of the batter for a nice visual effect.
- Bake for about 25 minutes, or until top is set. A toothpick inserted in the center should come out clean, or with a few moist crumbs, but no batter. Allow bars to cool in pan for at least 30 minutes before slicing and serving. Bars will keep airtight at room temperature for up to 1 week, or in the freezer for up to 6 months.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
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What’s the last pantry cleanout recipe you’ve made? What do you put in your Monster Bars?
I have these in the oven as we speak! They look awesome and the dough was delicious! ;-) I agree that they were very greesy. I added 1.5 cups flour instead of just one. Hope they turn out! They look like they will!
Thanks for trying them and I’m sure you’re going to love them!
Hi there…I made these bars yesterday and they are DELICIOUS! I had one problem though…they were very greasy/buttery on the bottom. I put them back in the oven thinking they weren’t quite done. Do you think they’d come out the same if I used less butter next time? Or maybe margarine? I served them with a paper towel on the platter and that helped to soak up some of the butter. Any suggestions will be appreciated. I’m definitely going to make these again! : )
Greasy..hmm, could have been the type/brand of PB used. I used Jif in mine. Or could have been the butter. You could reduce either the Pb or the butter, slightly, maybe 2 tbsp or so if you wanted. Or you could add maybe 2 to 4 tbsp more flour. Or you could bake them slightly longer. However, they’re not exactly a ‘light’ treat so some grease is normal :) But sounds like you would benefit most from slightly more flour. Lmk what you do when you remake them and how it pans out!
I would like to contribute the recipe for the cookie bars to our newest church cookbook. I made them for our homeschool back to school bash. I put them in my Longaberger bread basket and renamed them: “Schoolbox Brownies” – the colors reminded me of a child’s crayon box!
The bars were devoured, of course!
I would like permission to submit this great recipe! I would not be using any images.
Thanks,
Sarah Carroll
I think these sound and look incredibly delicious- but I have to say, I’m not sure how anyone has peanut butter M&M’s just left over without eating them. That never happens around here! :)
Lol – after writing a 100+ recipe PB cookbook, I have SO MUCH pb-related products in my house – you cannot even imagine :) I am always finding odds and ends! lol
I made these once and they were delicious!! …but I’m a fan of the orignal monster cookie so do you think you could substitute old fashioned oats for the flour? If so, would it be a 1:1 ratio of flour to oats?
If you’re talking cookies vs. bar cookies, it’s not that easy to just ‘swap’. This recipe was written to make these to be pressed into a pan, not baked as actual cookies and b/c there is no baking soda or baking powder, they would likely spread thin and flat and not work. If you wanted to use some oats in these bars, feel free to add a cup or so, and reduce the flour by maybe 3/4 cup.
If you’re looking for oatmeal cookies, I have at least a half dozen really solid oatmeal cookie recipes. Browse and then add your favorite add-ins to whichever base you choose. https://www.averiecooks.com/category/dessert/cookies
Sorry I wasn’t clear. I still want to make bars but i wasnt sure if it would work to use oats instead of flour. I will try adding 1 cup of oats and taking out 3/4 cup of flour. Thank you so much for your quick response! Very impressive
Oh WOW! These bars look intense :) I can’t wait to taste this
Wow!! These were amazing!!! Thank you so much for sharing this great recipe!!
Thanks for trying these, Amelia, and so glad they turned out amazing!
Outdoing yourself every time–I feel like I might be tempted to lick the kitchen sink after this, yick! :) thanks for sharing, Averie!
So sweet!
Pinning…these look FABULOUS!! Thanks for sharing! =)
Thanks for pinning!
I, too, am the Queen of The Freezer Full of Mismatched Quarter-full Bags of Candy, Nuts, and Other Miscellany! I do this all the time with cookies – just throw in everything. But from the looks of it, I am missing out by not using your bar base here, though. It looks divine.
Hi,
I just wanted to say that every recipe I’ve made of yours is wonderful! And these are possibly the best! I used your base, then added chocolate chips, white chocolate chips, sliced almonds, peanut butter cups, and marshmallows! So much for eating healthy for cross country, haha! But you are a very good baker and I plan to make most if not all of your recipes!
Thanks for LMK you’ve tried other recipes and these are your new fave! All your add-ins sound great! If I would have had any PB cups, I would have used those, too! Mmm, marshmallows – I bet they were a little bit like PB smores! If you try other recipes, please come back and LMK how it went!
You must know how much I love these cookies, they are fabulous! Thanks for linking up with What’s Cookin’ Wednesday!
I am trying to eat healthy during the weeks leading up to my wedding, but looking at this is making that a whole lot more difficult haha. They sound DELICIOUS! And I’m so glad you liked the Saint Paul post, I had an amazing time there and was just awestruck by the beauty while I was flying over the state. I definitely want to get back there to do some hiking!
I adored the post. Such a trip down memory lane – college, my family, my childhood. Thank for posting it and glad that MN was better than you thought it was going to be. If it wasn’t for the winters, it really is a wonderful place!
And congrats on your upcoming wedding!
These look perfect! Loaded and perfect!
I love just throwing in a whole bunch of leftover goodies into bars and cookies – they always taste great! Pinned and shared on FB this morning :)
Thanks for pinning and sharing! :)
So funny that you and Sally posted super peanut butter recipes on the exact same day! ;) Love it! I like my cookie bars dense and chewy and these look like they fit the bill. The outrageous pb flavor makes them even better!
She and I frequently post eerily similar recipes on the same day. Like yeast bread – rolls. One day I posted strawberry rolls and she posted another yeast roll, the same day. One day we’ll each post banana bread. We do it all the time!