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


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Peanut Butter Bars

A classic recipe that's perfect for parties and pot lucks since is makes a sheet pan full. Soft peanut butter cookie base, topped with creamy peanut butter and rich chocolate frosting.

Servings: 30
Prep Time 20 minutes
Cook Time 15 minutes
Total Time 35 minutes


  • 1 1/2 cups all-purpose flour
  • 1/4 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
Course: Dessert
Cuisine: American
Keyword: Frosted Peanut Butter Bars
Author: Jaclyn


  • 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

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

  • 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

  • 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

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