Peanut Butter Bars


WARNING: do not make these delectable bars unless you plan on sharing . . . or you will want to hoard and indulge in the entire sheet pan of them yourself! These are a childhood favorite of mine. I remember my oldest sister making them all the time and I remember how excited I was when I could smell the delicious scent of peanut butter coming from the oven and knowing what was ahead. The recipe my family has is the same recipe as the one I found to source the recipe (which is listed below the recipe). I have no idea where the original recipe ever came from but whomever came up with it, I love you!

peanut butter bars2

Simply put these peanut butter bars of joy are addictive. They are loaded with peanut butter, layered with oats, topped with more peanut butter and finished with a simple chocolate frosting. Now tell me, how could that not be good? I saw them going around Pinterest as “School Lunch Peanut Butter Bars.” Yes, I remember eating these bars at school lunch. Why do I remember? Because it was the only good thing that has ever been served at school lunch (most of my school lunch memories consist of the horror of those so called “meats.” Seriously, what is school lunch meat made of?). Most likely the actual school lunch version I had of these was prepared with margarine (which in my opinion should just become extinct) but butter makes everything better =). Somewhere in the near future I’d like to create a fancier version of these, but for now here is the classic version which many of you may remember from your childhood. Enjoy!

peanut butter bars



Peanut Butter Bars

Yield: 30 Servings

Prep Time: 20 minutes
Cook Time: 15 minutes


  • 1 1/2 cups all-purpose flour
  • 1/2 tsp salt
  • 1/2 tsp baking soda
  • 1 1/2 cups quick oats
  • 3/4 cup butter
  • 1 cup packed light-brown sugar
  • 1/2 cup granulated sugar
  • 1 1/2 cups creamy peanut butter , divided
  • 2 large eggs
  • 1 tsp vanilla extract

Chocolate Frosting

  • 1/2 cup butter
  • 2 Tbsp cocoa powder
  • 1/4 cup milk , preferably 2% or whole
  • 1 tsp vanilla extract
  • 3 1/2 cups powdered sugar


  1. Preheat oven to 350 degrees. In a mixing bowl, whisk together flour, salt, and baking soda, then whisk in quick oats, set aside. In the bowl of an electric stand mixer fitted with the paddle attachment, whip together butter, light-brown sugar and granulated sugar on medium-high speed until pale and fluffy, about 3-4 minutes. Blend in 3/4 cup peanut butter. Stir in eggs one at a time, mixing after each addition until combine. Mix in vanilla. With mixer set on low speed, slowly add in dry ingredients and mix until combine. Spread mixture into an even layer into a greased 15 by 11-inch rimmed cookie sheet (it will be fairly thin once spread). Bake in preheated oven 13 - 15 minutes, until lightly golden. Remove from oven and allow to cool 5 minutes, then dollop remaining 3/4 cup peanut butter by the spoonfuls over peanut butter bars. Allow dolloped peanut butter to rest about 1 minute then carefully spread peanut butter into an even layer over top. Prepare chocolate frosting according to direction listed and spread over peanut butter layer. Allow to cool (if you can handle waiting) before cutting into squares. Store in a single layer in an airtight container at room temperature.
  2. For the chocolate frosting:
  3. Melt butter in a medium saucepan over medium heat. Whisk in cocoa powder, then whisk in milk and bring mixture just to a boil. Once mixture reaches a boil, remove from heat and stir in vanilla extract. Add in powdered sugar and mix until well blended. Immediately pour frosting over peanut butter layer and spread into an even layer (frosting sets quickly so I wouldn't recommend being to meticulous with the design like I tried to be, because then you'll end up with a slightly grainy looking frosting like I did).
  4. Recipe Source: adapted slightly from Tried and Tried Again


  • Chung-Ah | Damn Delicious: Sorry, I just can’t share these! I am going to totally hoard every single one of these! January 28, 2013 at 11:40pm Reply

  • Jackie: I love the design on top! Can I ask how you did it? It’s so neat and perfect! January 29, 2013 at 1:01am Reply

    • Jaclyn: Thanks Jackie – I actually felt like I totally screwed it up =), I was going to remake them so I could do the frosting better but I got too lazy about it and I couldn’t handle having another sheet pan full of them in my house 1 pan was dangerous enough. Anywyay I just used an icing spatula and basically waved it up and down back and forth. I originally tried this type of technique which I love: but the frosting sets up so fast it just didn’t work out with this kind of frosting and I ended going over it and making it grainy. Thanks for your nice comment =)! January 30, 2013 at 1:27pm Reply

  • annie: these look really yummo-i’m gonna have to make these!! thanks for sharing :) January 29, 2013 at 4:33am Reply

  • Kayle (The Cooking Actress): Ooooh omg these DO look dangerous! I dunno if I’ve ever had them-apparently I was severely deprived as a child. January 29, 2013 at 8:06am Reply

  • Shannon: It must be a sign… my hubby was just commenting on how much PB we have in the house… and I have all these ingredients on hand. Thanks for the divine intervention! :-) January 29, 2013 at 11:53am Reply

  • Amanda: These sound amazing!! Making ASAP! :) January 29, 2013 at 1:06pm Reply

  • Kristy @ Sweet Treats & More: Okay, seriously! I’ve been craving peanut bars and was just about to make them yesterday!! I think our recipes are pretty similar. Great taste we have:) January 29, 2013 at 3:17pm Reply

  • Jessica@AKitchenAddiction: I would definitely be hoarding these! January 29, 2013 at 3:42pm Reply

  • Ramona: I can see why they are addictive!! Love peanut butter and chocolate together anytime. :) January 29, 2013 at 3:49pm Reply

  • angela @ another bite please: hahaha school lunch…wow was that a wave of memories flash through my mind…i love peanut butters…and agree must share or i would go crazy sick eating the whole pan! January 29, 2013 at 5:09pm Reply

  • Kat: Nope. Not sharing. January 30, 2013 at 11:00am Reply

    • Jaclyn: It really is hard with these =) January 30, 2013 at 1:03pm Reply

  • Loretta | A Finn In The Kitchen: I’m so with you on margarine. It can go in a corner and die for all I care. Unhealthy and tastes weird. Not much going for it…

    I totally remember these bars too! I kind of forgot about them, so thanks for bringing them back! Pinning…. January 30, 2013 at 3:46pm Reply

    • Jaclyn: Thanks for your comment and pin Loretta! January 30, 2013 at 5:36pm Reply

  • Lisa: Jaclyn, Do you think I could substitute the cocoa powder with by melting chocolate chips? If so, how much do you suggest? And would I still need the icing sugar? January 31, 2013 at 9:15am Reply

  • Wendy: I was wondering if it would still turn out while using a hand electric mixer. I don’t have one of those nice big ones :( February 3, 2013 at 7:16am Reply

    • Jaclyn: Wendy – I usually tell people yes most of the time it works fine but once your hand mixer can’t handle it anymore (it starts to slow and sound heavy) stop and mix the rest by hand so you don’t burn out the motor on your hand mixer. I hope you enjoy! February 4, 2013 at 8:32pm Reply

  • Sandi @ My Culinary Escapades: These look amazing. Chocolate and peanut butter is my favorite combination. February 3, 2013 at 3:30pm Reply

  • Julia: Ready to start all I need to know now what size to you cut them to get 30 servings out of a 11 X 15 pan March 13, 2013 at 4:09pm Reply

    • Jaclyn: I think it was 5 rows of 6? It makes a lot =). March 14, 2013 at 4:03pm Reply

  • Lauretta Grove: I will take these to the next church meeting. ummmmmmmmm. March 13, 2013 at 5:56pm Reply

  • Debbie: I always loved the peanut butter bars from school lunch. However, ours had a peanut butter frosting. Does anyone have a recipe for a peanut butter frosting to use instead of the chocolate frosting? March 31, 2013 at 7:08pm Reply

  • Jessica: These look so yummy!! I’m pretty sure these are the same ones I had at school, too.
    Would these work as sugar-free as well? I’m concerned with the topping the most…would it work best to make a sugar-free chocolate icing with direct subs for your ingredients, or use melted sugar-free chocolate chips? Thanks! :) April 8, 2013 at 12:28pm Reply

    • Jaclyn: You may want to go with the sugar free chocolate chip as I’m not sure how the sugar free subs would work with this icing recipe. I know sometimes adjustments have to be made if using other forms of sweetener. April 14, 2013 at 5:11pm Reply

  • T: Hi, is it really 3 1/2 cups of powdered sugar for the chocolate frosting? It sounds like a huge amount. April 20, 2013 at 10:57am Reply

    • Jaclyn: Yes that is how much I used. April 20, 2013 at 10:25pm Reply

  • Holly @ EatGreatBEGreat: I MUST try these PB bars! They sound fantastic! Pinning this one! April 30, 2013 at 2:55pm Reply

    • Jaclyn: Thanks for the pin Holly, I hope you love them! April 30, 2013 at 7:46pm Reply

    DELICIOUS. MY FAMILY LOVES IT! May 13, 2013 at 9:22am Reply

    • Joan Peterson: Could you share this recipe with us? That one sounds delicious as well. Thanks. July 9, 2013 at 2:35am Reply

  • Kelsey: I made these without a mixer of any kind, I just used my arm. They turned out amazing! Thank you for sharing this recipe, especially since it’s ingredients I usually have around. Pinned them for future peanut butter cravings. July 16, 2013 at 6:59pm Reply

  • ShaNae: Hi,
    For the frosting, the cocoa powder, is it sweetened or unsweetened?
    ShaNae August 7, 2013 at 11:05am Reply

    • Jaclyn: It’s unsweetened, sorry should have noted that. August 7, 2013 at 1:50pm Reply

  • Beatrice: Tried them out this weekend. They tasted great.
    We were on a road trip and we almost ate the entire batch.
    But my chocolate frosting did not set so well. I was wary about using 3.5 cups sugar for the frosting, did not use it all, so that could be the reason.

    Is there another frosting i could try out that uses less sugar, because I definitely will keep baking these. October 29, 2013 at 3:14pm Reply

  • Reica: Is there another sized/type of pan I could use to bake then in? I don’t have one if those big ones. February 26, 2014 at 3:05pm Reply

    • Jaclyn: I would probably recommend halving the recipe and then baking them in a 9 by 9, 8 by 8, or a 7 by 11. You might have to bake them a little longer for the 8 by 8 or 7 by 11. March 4, 2014 at 9:27pm Reply

  • Dawn: Will old fashioned oats ruin the recipe? September 14, 2014 at 6:25pm Reply

    • Jaclyn: They’d probably have a different texture but they might work? I haven’t tried with this recipe so I can’t say for sure. September 30, 2014 at 6:54pm Reply

  • Chris Tollison: I would like to know HOW WELL DO THESE KEEP IN THE FREEZER ? I have been making these for awhile now and are VERY GOOD !!!! ♡ August 31, 2015 at 7:12am Reply

  • Chris Tollison: Do these FREEZE WELL ?? August 31, 2015 at 10:35am Reply

  • CAC: Can these be frozen?
    Made a pan, were a great hit but a few leftover.
    Wondering if they can be frozen for a treat later?? February 20, 2017 at 1:15pm Reply

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