These Peanut Butter Cookie bars are reminiscent of a retro dessert that used to be served at many cafeterias across the US! They’re incredibly soft, rich in peanut butter flavor, with bite from some added oats, and covered in a smooth and rich chocolate icing. My favorite thing about this recipe (besides how good they are) is how many they make. They bake up in a sheet pan, and because they’re rich, you can cut them fairly small, so it’s the perfect dessert to feed a crowd. I often take them to parties and potlucks because of this (as long as I’m sure it’s a function that’s safe for peanut recipes!)
Ingredients and Equipment List
- Peanut Butter – you can use creamy or chunky peanut butter. I’ve never tried this recipe with a natural peanut butter (if you do, let me know!) But standard brands like Skippy and Jiff work great.
- Butter – unless you have an allergy or food intolerance, I recommend real butter (salted).
- Sugars – you’ll use a combination of granulated white sugar and light brown sugar.
- Oats – quick oats give these bars extra chew. If you don’t have quick oats, I like to pulse my old fashioned oats in the blender a few times to break them up just a bit.
- Cocoa Powder – cocoa powder is used in the icing, and you’ll want to used unsweetened.
Instructions
These cookies are incredibly quick and easy to whip up. It’s simply a basic cookie dough, frosted with the icing while it’s still warm.
- Make Dough: This is standard cookie making procedure here. You’ll cream together butter and sugar, then add peanut butter, eggs, and vanilla.
- Whisk together your dry ingredients and add those until combined.
- Stir in the oats.
- Press into a parchment-lined baking sheet and bake.
- Now, right here there’s an optional step: If you want to go full send, you can also drizzle on some melted peanut butter on top of the warm bars so there’s a layer of peanut butter underneath the chocolate icing. I used to always make them that way, and it’s deliciously indulgent, but I think they’re equally fantastic (and a little less rich) with out the PB layer so I usually skip that step these days.
- Mix up your frosting and spread on top of warm bars.
- Wait until they’re cool to slice!
Frequently Asked Questions
- Can these be made ahead of time? YES! They are are actually extra great made ahead of time (dare I say better on day 2?) Since they’re super soft they just seem to get better. You can cover the cooled pan in foil or plastic wrap and cut on day 2, or keep the sliced bars in an airtight container. I would also imagine they freeze well, though I haven’t tried that.
Chocolate-Frosted Peanut Butter Cookie Bars {Aka: School Lunch Peanut Butter Fingers}
Unbelievably soft and chewy peanut butter cookies in bar form, topped with a rich chocolate glaze. Made in a sheet pan for high yield!
Ingredients
- Cookie Base1 cup real butter 2 sticks at room temperature1 cup granulated sugar2 cups brown sugar1 1/2 cups peanut butter, chunky or smooth 3 eggs2 teaspoons vanilla1 1/2 teaspoons baking soda1/2 teaspoons table salt3 cups all purpose flour3 cups quick oatsoptional: an extra 3/4-1 cup peanut butter, see notes in recipe below
- Fudge Frosting4 cups powdered sugar1/2 cup cocoa powder1/4 teaspoon table salt1/3 cup butter softened1/3 cup boiling water1 teaspoon vanilla extract
Instructions
- Preheat oven to 350 degrees. Spray a rimmed cookie sheet (standard half-sheet pan) lightly with non-stick spray, or line with parchment paper, and set aside.
- Cream butter and sugars for 3-4 minutes, until creamy and slightly fluffy. Add peanut butter and vanilla and beat until combined. Add eggs, one at a time and beat between each addition. Combine flour, baking soda, and salt and add mixture to dough. Beat to combine. Add oats and mix until incorporated.
- Press dough into prepared pan into a flat layer. Bake for about 20-30 minutes, until puffed and set, but not browned on the edges. The center should be puffed and set, but still soft. The edges of the cookie bars should be puffed and kind of cracked like a baked cookie looks.
- Optional Step: Some people like to drizzle on a layer of melted peanut butter onto the warm bars so there's a layer of pb under the icing. If you'd like to do that step, I just microwave 3/4-1 cup of pb until it's melted and smooth and can easily be drizzled over the top of the warm bars. You'll want to spread it gently so you don't tear your cookie layer. It's deliciously indulgent with or without this extra pb layer!
- When cookies are just about done, prepare frosting. Whisk together powdered sugar, cocoa powder and salt. Add butter (make sure it’s really soft, you can microwave it if you need to- even melted is ok!), boiling water, and vanilla. Beat until smooth and glossy.
- When cookie crust is done baking, pour warm frosting over the top and spread into an even layer. Let bars cool before cutting in.
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Questions & Reviews
I was LOOKING for a recipe that was like the bars I used to have in elementary school (Cannon AFB, Clovis, NM)I used to LOVE them. Been looking for the recipe for years, and yours looks the closest, although I think they might have used melted chocolate instead of frosting, cause the top was firm. I seem to remember the inside having rice crispies instead of oats, but I will try this recipe, it looks delicious!
Oh, I used to LOVE lunch lady peanut butter bars! I haven’t had one since I was little (thank you, Quail Hollow Elementary) but I saw some when I was in Macey’s today and remembered I’d seen your recipe here. I came straight home and made them, and they are wonderful. A 2/3 batch exactly fit my 15 inch sheet pan, and they were super easy to put together. I was a little skeptical about the ten minute baking time, but they came out perfect. Crisp edges and bottom, but so soft and moist inside. My gosh, what a treat. I’ll have to take some over to my sisters and see if they remember eating them in school. Thanks a mil!
This looks delicious! I’m going to have to try this!
I’ve been looking for this recipe forever. Thanks for posting it. I can’t wait to make these!
I have made these a ton and to help with the texture issue I have found (by accident) if you cook them half way then stir up and press back into pan they have more of a bars mixture rather than soft cookie. Oh yeah and the frosting is way better than just chocolate chips and peanut butter.
This really did taste like ones we would get with our school lunches, which was exactly what I was looking for. Thanks so much for sharing! 😀
This recipe is good! Too good…I’m pretty sure it’s the culprit for a few gained pounds. 🙂
These have become my go to for potluck treats! Thanks for the recipe, they are amazing!
I totally forgot about these! Its been like 15 years since elementary, and when I made these tonight – it was like taking a bite into my childhood! Too bad you will probably never see these in a school again – too much sugar and peanut allergies . . . boo. 🙁
I can’t wait until my hubby gets home for work and tries these – he will think I am the best wife ever!!!
Yay!! Peanut butter bars “like the school makes” are my daughter’s absolute favorite and I’ve never been able to duplicate them at home for her. This recipe looks like it might be it. Can’t wait to try it.
I noticed above you said 13 X 18. My pan is definitely not that size.
Ya, it sounds like your pan is a little small. Hopefully it doesn’t spill over, just bake them a little longer!
Ok… I ended up cooking them longer to account for my pan size and they are still great tasting. I don’t know how the consistency will hold up for tomorrow though. I am afraid they will get too hard.
So I have these baking in the oven right now. I used what I consider a standard size cookie sheet and the dough filled the cookie sheet right up to the rim before it was baked. I double checked the measurements and am nervous I put it in too small a pan. Help! Is your “standard cookie sheet” a sheet cake pan? I measured mine and it is 12 X 16.
My wife is making this right now and I am helping give her the instructions. She made them a month ago and I gave them to my clients on the river as part of there lunch…they are mmmmm good.
My mother in law makes her famous peanut butter bars on special occasions and they are delicious! I do believe however that you have created an even better recipe that is to die for! I followed your recommendation to eat these with vanilla ice cream…YUM!! I had to send half the pan to work with my husband so I didnt eat them all! Tomorrow is going to have to be a strictly water and veggies day to make up for eating so many today!
Made these tonight for our special Sunday dessert and they were delicious! For the future I was thinking of cutting them all up in about the same size and freeze them for my kids school lunches and pull them out when I need them!
This is my first time to your site, you come highly recommended by a friend.
I have been searching for this recipe for years, and I am so excited to find it! They have started making these at Golden Corral so I like to go there just to get my school lunch peanut butter bars fix! =0)
Also, I can’t believe that the above lunch lady said they made them stop making these bars because they were unhealthy. It’s so ironic looking at the school lunches they serve now…pizza, chicken nuggets, corn dogs etc. You can’t get much more un-healthy than school lunch in my oppinion!
I made these lastnight and they were divine!!! I don’t know if I did something wrong, but I couldn’t add all the oats. My dough was so thick I could only add one of the three cups. Are all the measurements right? It could have been the organic peanut butter I used, but other than that I did it all according to the recipe. I loved it and it still turned out great, thanks for sharing!
I’m guessing it was your PB because I’ve never had that problem, but I’m glad they still turned out great!
I made these a few days ago. They are amazing! Makes a ton, so plan on sharing with neighbors!!
I made these tonight, I live in the Seattle area so the opposite altitude of the above post, and mine were really soft too. My kids and I loved them, but they tasted like delicious cookie dough rather than cookies. If I cook it like 18-20 minutes will they firm up? Or is that just the texture?
you can definitely bake them a little longer, but the texture really is dough-y soft 🙂
I was so excited to make these as chocolate and peanut butter and cookies are my ultimate favorite combination. Mine didn’t turn out, though. 🙁 I live in Albuquerque, at about 5,000 ft and am wondering if the altitude had something to do with it? I even baked them for 5 or so minutes longer because they didn’t look done at all at 10-12 min. Sigh. If you have any high altitude baking tips, it would be greatly appreciated!
You could try cooking them a little longer, sorry I’m not much help with high altitude!
My Lunch lady peanut butter bars recipe says to bake for exactly 20 minutes, and I live at 4800 ft. Hope it helps!
I made these for a scout pack meeting and the parents and kids all raved about them. Thanks for the recipe. This will be a new favorite at our house! 🙂
i soooo wish i had went to the same school as y’all because we never had anything this yummy! lol! i have to say i made these for a pool party we went to & they were a HUGE hit. everyone loved them & asked for the recipe. making them again today but was wondering if i could by any chance leave out the oats? they were awesome w/oats but also wanted to try without. and this is by far the EASIEST & BEST chocolate frosting EVER! loved it & even made just the frosting the other day to top some mini fudge brownie bites i made. delicious! hugs & thanks for all the amazing recipes!
You know you are the devil for giving me this recipe. I once volunteered to be an election judge because I knew the voting location would be at a school and there would be an off chance go scoring one of these bars. It totally worked. Yeah. It was delicious and totally worth the 18 hour day I had as an election judge.
I just made these today for company tonight- but just had a taste. They are SO good! Love the frosting. I skipped the extra pb step and they are still so good. I used natural pb (Smart Balance) and cut the recipe in half- using a half-sized jelly-roll pan. When baking recipes get cut in half and call for 1 1/2 eggs, I always use 1 whole egg and one egg yolk- seems to work well.
Shoot, I just noticed it calls for “quick” oats and don’t have any. Can I use regular oats and just extend the baking time?
I thought I didn’t have quick oats and used the regular, they were just a little more chewy and the baking time didn’t need to be extended or anything, so use them and enjoy!
Has anyone made these with 100% natural peanut butter, such as “Adams”? Just wondering if it would change the taste of the recipe? I’ve never cooked with natural peanut butter, but I like it on PB&J sandwiches b/c it’s so much healthier.
I think I just drooled …
Where has this recipe been all my life??? I made these and they were a huge hit. I couldn’t stop eating them. I have a recipe of a PB bar from the Lion house and they do not compare to these. They definetly reminded me of the one’s we use to get for school lunch. I am so glad now I finally have a good recipe!! Thanks so much.
Oh my goodness. Seriously, this was meant to be! I have been craving these for a couple weeks, and just couldn’t find the ‘school lunch’ version that I was looking for. Lets be honest, when you’re 39 weeks pregnant and having a craving for something specific, there’s no point wasting time making something sub-par. I can not wait to make these! 🙂 Thanks again!
Not sure what I did to ruin these… maybe it was the pan I used, but PLEASE tell me you try something you think will be fabulous and it turns out like a disaster?? If that happens to the pro’s, then I will keep on trying to get something right!
Us?? No never. Everything we make is perfection.
Ha! We’ve had our share of kitchen disasters. Try, try again!
Just made these today. Couldn’t be bothered with very precise conversions to metric measurements, and also I cut down on the sugar, but they turned out very well, and very “American”, I imagine! Here in Norway, we normally cook everything to death so I couldn’t help myself; I left the pan in the oven for 5 minutes extra. But they are still soft and gooey inside – I guess it has something to do with my bars being much thicker than yours. I may have taken too lightly on converting the inches for the pan as well as the cups for the recipe … 😉