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 {School Lunch Peanut Butter Fingers}
Unbelievably soft and chewy peanut butter cookies in bar form, topped with a rich chocolate glaze, just like the ones you remember! Made in a sheet pan to feed a crowd.
Servings
Equipment
Ingredients
For the Cookie Base
- 1 cup real butter 2 sticks at room temperature
- 1 cup granulated sugar
- 2 cups brown sugar
- 1 ½ cups peanut butter chunky or smooth
- 3 eggs
- 2 teaspoons vanilla
- 1 ½ teaspoons baking soda
- ½ teaspoons table salt
- 3 cups all purpose flour
- 3 cups quick oats
- ¾ – 1 cup peanut butter optional, see notes in recipe below
For the Fudge Frosting
- 4 cups powdered sugar
- ½ cup cocoa powder
- ¼ teaspoon table salt
- ⅓ cup butter softened; make sure it’s really soft, you can microwave it if you need to – even melted is ok!
- ⅓ cup boiling water
- 1 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 peanut butter under the icing. If you'd like to do that step, I just microwave 3/4-1 cup of peanut butter 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.
- When cookies are just about done, prepare frosting. Whisk together powdered sugar, cocoa powder and salt. Add butter, 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.
Notes
The nutritional information was calculated according to cutting the sheet pan into 36 bars.
These are best made 1 – 2 days ahead of time.
Nutrition
Calories: 303kcal, Carbohydrates: 48g, Protein: 6g, Fat: 11g, Saturated Fat: 3g, Polyunsaturated Fat: 2g, Monounsaturated Fat: 5g, Trans Fat: 0.1g, Cholesterol: 18mg, Sodium: 186mg, Potassium: 167mg, Fiber: 2g, Sugar: 32g, Vitamin A: 72IU, Calcium: 27mg, Iron: 1mg
Calories: 303kcal
Cost: 7
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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.