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Retro-style Lunchroom Chocolate Peanut Butter Bars…taking it back to grade school today with these DELICIOUS peanut bars. Picture a doughy buttery, peanut butter cookie base, layered with creamy peanut butter, and the most delectable, roll your eyes back good chocolate frosting that’s rich and fudgy. The added bonus is that these bars require only pantry staple ingredients and take almost no effort to make. They’re sweet, salty, heavy on the peanut butter, extra chocolatey, and every last bite is truly delicious. The perfect treat to enjoy as an afternoon/after-school/homeschool snack and for any upcoming fall gatherings with family or friends.

The truth really is that I love each and every recipe I share with you guys. I work endlessly to only share the best of the best with you guys. There are many, many…and I do mean many…recipes that you never see because they just aren’t good enough. The recipes I share with you guys have to be really good, so because of this, I love them all.
That said, I of course have some recipes I might favor slightly more than others.
Case in point, these peanut bars. It’s no secret that my favorite desserts include chocolate and peanut butter. That’s fairly obvious from the amount of peanut butter and chocolate recipes that can be found on the site. I could not love these chocolate frosted peanut bars more. If you could see me typing away, you’d see my excitement
It’s dorky, I know, but I love it when I really LOVE a recipe. That said, I have so many reasons why I love this recipe…and it’s not just about the taste.

So here comes the story.
I’ve been talking about this all week, but it’s back to school time, and for me, that brings back a lot of feelings. For as much as I hated school growing up, I always somewhat enjoyed this time. Back to school meant, new clothes, new supplies, and the excitement of the fall season ahead.
And also? Lunchroom desserts. YES, you guys know what I’m talking about.

For me personally, I never bought a school lunch. Mom always packed our lunches when we were younger. But the one thing we did always get to enjoy was pizza day. Oh, pizza day. If I’m remembering correctly, it only happened once a month (if not it seemed like it was a month!). It was a day we looked forward to all month long. We loved pizza day!
I mean of course, we got to eat cheesy pizza (yumm), but even better than the pizza?
The “lunchroom” desserts that came with it. Also known as the desserts that all the PTA moms would bring in. Enter the giant chocolate chip cookies and the generously frosted chocolate peanut butter bars. Again, yumm!
Today I took inspiration from my grade school days and really thought back to what I loved most about those “lunchroom” peanut bars.
They were doughy, heavy on the peanut butter, and frosted with the most delicious fudgy chocolate frosting. The frosting was a cross between fudge, frosting, and icing. Hard to explain, but I get the feeling many of you know what I’m talking about.
Who else enjoyed a good ole’ chocolate peanut butter bar on pizza day? Any of you? I can’t be alone on this one.

Lunchroom Chocolate Peanut Butter Bars…the details.
For once, this dessert didn’t take me forever to perfect. Though I did have to make the frosting about four times to get it JUST right.
These bars are easy…so easy…and very hard to mess up.
Start with the peanut cookie base. I used my favorite blondie recipe that’s pretty much foolproof. It doesn’t even require a mixer, just mix with a spoon and bake. So simple. As soon as the peanut bars come out of the oven, dollop them with a hefty amount of creamy peanut butter. The key is to add the peanut butter while the bars are still warm. The heat from the bars allows the peanut butter to melt into one even layer and make spreading the peanut butter out very simple.
Now let the bars chill completely.

In the meantime, make the frosting.
I have some words on this frosting.
When I set out to make these I had a picture of the frosting in my head and I needed to recreate that picture. The frosting needed to be thick and fudgy, but yet soft and almost runny. Think of a just set top that has glazed over and stiffened, but then underneath is fudgy, loose frosting.
Very old school, very vintage, that’s what I was going for. Like the kind of frosting your grandma would make.

Yummm (apparently, this is today’s word of the day. Just go with me on it).
What is the secret?
The mix of ingredients is basic…butter, sugar, cocoa powder, vanilla, and milk.
So what’s the trick? Using warm to almost hot milk. The heat from the milk warms the butter and turns the cocoa powder into a rich creamy chocolate. It’s so hard to explain, but I promise, it’s beyond good. Just sweet enough, extra chocolatey, smooth, and very fudgy.
Once the bars are cooled, just spread the frosting over top. And that’s it, easy.
You can let the frosting set up or just cut and enjoy, preferably with cold milk, because that’s the best pairing with chocolate and peanut butter.

Nothing too fancy, but all things incredibly delicious.
I know that things look different this year. But whether you or your kids are heading back to the classroom, or just homeschooling, these bars make for the perfect dessert to enjoy anytime, mid-school day, after school, late night. They all work. Just bake, eat, and enjoy all the deliciousness.
And if your kids are home, these are easy enough for them to help bake up too!

Looking for easy “lunchroom” style back to school desserts? Here are a few ideas:
Chocolate Peanut Butter Pretzel Blondies
Giant Salted Espresso Hot Fudge Cookies
Lastly, if you make these lunchroom chocolate peanut butter bars be sure to leave a comment and/or give this recipe a rating! Above all, I love to hear from you guys and always do my best to respond to each and every comment. And of course, if you do make this recipe, don’t forget to tag me on Instagram! Looking through the photos of recipes you all have made is my favorite!
Lunchroom Chocolate Peanut Butter Bars.
Servings: 24 bars
Calories Per Serving: 344 kcal
Nutritional information is only an estimate. The accuracy of the nutritional information for any recipe on this site is not guaranteed.
Ingredients
- 1 1/2 sticks (3/4 cup) salted butter
- 2 cups creamy peanut butter
- 3/4 cup light brown sugar
- 1/4 cup granulated sugar
- 2 large eggs, at room temperature
- 1 tablespoon vanilla extract
- 2 cups all-purpose flour
- 1 teaspoon baking powder
- 1/2 teaspoon kosher salt
Frosting
- 1 stick (1/2 cup) salted butter, at room temperature
- 2-3 cups powdered sugar
- 1/2 cup cocoa powder
- 2 teaspoons vanilla extract
- 1/4 cup warmed milk
Instructions
- 1. Preheat the oven to 350 degrees F. Line a 9×13 inch baking dish with parchment paper.2. In a microwave safe bowl, melt together the butter and 1/2 cup peanut butter, stirring every 30 seconds until melted. Stir in the brown sugar, sugar, eggs, and vanilla. Add the flour, baking powder, and salt. 3. Press/spread the dough out into the prepared dish. Transfer to the oven and bake for 18-22 minutes, until just set in the center. Remove from the oven and dollop tablespoon size spoonfuls of the peanut butter over the bars, lightly spreading the peanut butter in an even layer. Let cool completely. 4. To make the frosting. Add the butter, 2 cups powdered sugar, cocoa powder, vanilla, and 1/4 cup warm milk to the bowl of a stand mixer. Beat until smooth, adding additional warm milk until the frosting becomes thicker, but still drizzly. Taste, adding more sugar if needed. Spread the frosting over the bars. Let set for 1-ish hour…or slice, snack, and enjoy!
Notes
To Make Gluten Free: Use an equal amount of your favorite gluten free flour blend in place of the all-purpose flour. I recommend Cup4Cup gluten free flour.
Storing: these bars keep well for 3-4 days at room temperature or in the fridge.
To cool the bars quickly for frosting: place in freezer for 15 minutes. Remove and frost.
To Bring Eggs to Room Temperature: place the eggs in a bowl and fill with warm water. Let sit 5 minutes.

Made these today gluten free with cup 4 cup. Followed the rest of the recipe exactly. They are AMAZING!!
Awesome! So glad you were able to modify this recipe to your needs! xT
I made these, so yummy! I left the cookies in for the full 22 minutes, but I wish I had taken them out a little bit earlier. Also, I skimped out on the peanut butter middle layer because I didn’t have much but they definitely would have benefitted from the full amount!
Thank you for giving these peanut butter bars a try! xT
These are delicious and so easy to make.I will definitely make these again! All your recipes are winners!
Thank you Marlene! So glad you’re loving these! xT
Hi! Would almond milk work okay for the frosting?
Hi Bella,
Yes, that would work well for you! Please let me know if you give this recipe a try, I hope you love it! xT
Do these freeze well? Thanks!
Hi Christy,
Yes, these would be just fine for you to freeze! Please let me know if you have any other questions, I hope you love this recipe! xx
These bars are so crazy delicious. I replaced the butter in the peanut cookie base with olive oil and they turned out great. Yum! Thank you for another amazing recipe.
Hey Jessica,
Amazing!! Thanks so much for making this recipe and your comment, so glad it was a hit! xT
Made these today and they came out perfect! I used my convection oven and shortened the baking time to 13-14 minutes. The base layer is moist and a cross between cake and cookie.
I added about 1/2 cup more powdered sugar to the 2 C powdered sugar and added about 1/8 C more warm milk to the 1/4 C milk to get the super creamy glory icing you have in your photos. Sooo good!
Hey Penny,
Wonderful!! I love to hear that this recipe was enjoyed and appreciate you giving it a try! Have a great weekend! 🏈
Made these for Christmas two years in a row. Easy and tasty! Think this recipe may be an annual tradition.
Hey Robyn,
Happy Wednesday!!🎇 I am delighted to hear that this recipe was enjoyed and appreciate you making it! xx
Hi! Just wondering what type of peanut butter would work best for these? Is it okay to use all natural or would something like jif work better?
Hey Megan,
I like to use a natural peanut butter here, so this should be just fine for you to use! Please let me know if you have any other questions! xT
SO good!!!! I just made these for a Christmas party and when I tell you they were a hit, literally every person in attendance pulled me aside at different times just to compliment me on them and ask for the recipe. 10/10!!!
Hey Kendall,
Happy Wednesday!! I truly appreciate you giving this recipe a try and sharing your review, so glad to hear it was a hit:)
My husband made these for a family gathering (pre pandemic) and now everyone wants him to make these again for the holidays. This recipe is a 10+
Hey Carol,
Awe, I love to hear this!! So glad everyone has been enjoying this recipe, thanks for sharing:) xx
Tastes great, but the cookie layer and the icing layer didn’t turn out like the video or pictures for me. I cooked my cookie layer for 18 mins and it was pretty crumbly/dry. I had hoped it would be chewy, but it was still tasty. My icing was delicious, but didn’t look the same as the pics or video. I think some of the variability could be due to how I measured the flour and powdered sugar.
Hi Kay,
Happy Wednesday! Thanks so much for making this recipe and sharing your feedback, so glad to hear it turned out well for you! xTxT
Darn! Mine came out dry and the frosting was more like a fluffy buttercream and not runny/shiny. I’ve loved most of the HBH recipes, so on to the next one!
Hi Jenna,
Thanks so much for giving this recipe a try, so sorry to hear you had issues! Let me know if there is anything that I can help with! xTieghan
Can you sub almond flour for the all-purpose or will it change the taste too much
Hi Emily,
I think gluten free flour blend would work best for you! Please let me know if you give the recipe a try, I hope you love it! xx
Hi wondering … it says butter add the butter to the batter in the first step and then below for frosting it says it again.. add the butter. How much for each step? Is it 1.5 sticks total so 1 stick for frosting and 1/2 for the batter??
Hi Gia,
The recipe calls for 1 1/2 sticks of butter in the batter and 1 stick in the frosting. Please let me know if you have any other questions! xx