This post may contain affiliate links, please see our privacy policy for details.

Bake Sale Peanut Butter Oat Bars. Think a doughy, buttery peanut butter cookie base made with old-fashioned oats, baked until just set, then layered with creamy peanut butter. On top, a rich chocolate frosting is poured over the bars to sandwich in all that peanut butter goodness. Once the frosting sets, it creates that old-fashioned crackly icing we all know and love. These bars are chocolatey, peanut buttery, and so delicious!

Bake Sale Peanut Butter Oat Bars | halfbakedharvest.com

Iโ€™m back today with even more bake saleโ€“inspired treats. Iโ€™m honestly not even sure if bake sales are still much of a thing, but I love baking up sweets that are perfect for sharing this time of year.

Bake sale or not, these are the bars to bring for game day, family parties, or dinners with friends. Itโ€™s that time of year when everyoneโ€™s starting to gather again after a summer of fun and easy nights.

Inspired by the peanut butter oat bars our school lunchroom used to serve, these are guaranteed to be a hit with everyone. And if you do end up baking them for the school bake sale, theyโ€™ll definitely be the first treat to disappear.

Bake Sale Peanut Butter Oat Bars | halfbakedharvest.com

These are the details

Ingredientsย 

  • salted butter
  • creamy peanut butter โ€“ crunchy will work too!
  • brown sugar
  • vanilla
  • eggs
  • vanilla extract
  • flour
  • old-fashioned oats
  • baking soda

For the Icing

  • powdered sugar
  • cocoa powder
  • vanilla
  • ย dark or milk chocolate โ€“ I love dark

Special Tools

For these peanut butter bars, you need two mixing bowls and an electric mixer. I love this half sheet pan for baking.

Bake Sale Peanut Butter Oat Bars | halfbakedharvest.com

The Steps

Step 1: Make the cookie dough

In a mixing bowl, beat the butter together with the brown sugar, peanut butter, and vanilla. Add the eggs and beat until combined. Mix in the flour, oats, baking soda, and salt.

Mix, mix, mix until you have a soft dough!

Bake Sale Peanut Butter Oat Bars | halfbakedharvest.com

Step 2: Bake

Line a 9ร—13-inch baking dish with parchment paper. Or, if you prefer thinner bars, use a slightly larger half sheet pa, something are a 13ร—18 inch half sheet pan.

Bake for about 20 minutes (22 minutes if using a sheet pan), until just set.

Bake Sale Peanut Butter Oat Bars | halfbakedharvest.com

Step 3: The peanut butter layer

As soon as the bars come out of the oven, spread the remaining peanut butter evenly over the top. The heat from the bars will melt the peanut butter, making it easy to spread into a smooth layer.

Let the peanut butter stiffen and set. To speed things up, pop the pan in the fridge or freezer until firm.

Bake Sale Peanut Butter Oat Bars | halfbakedharvest.com

Step 4: The chocolate icing

Whisk together the powdered sugar, cocoa powder, vanilla, and melted milk chocolate until smooth and fudgy. Pour the icing over the bars and spread evenly.

Let the icing set and harden, or dig in right away while itโ€™s still gooeyโ€”so delish!

Tip

If youโ€™d like a shiny, glossy finish to your icing, whisk in a couple teaspoons of meringue powder. It helps the frosting set without smudging. Totally optional, but a fun extra!

Whether itโ€™s back-to-school, game day, or just a family night in, these bars are the perfect dessert to bake, share, and enjoy. And if youโ€™ve got kids around, this is an easy recipe they can help with too!

Bake Sale Peanut Butter Oat Bars | halfbakedharvest.com

Looking for easy โ€œlunchroomโ€ style back-to-school desserts? Here are a few ideas:ย 

Crinkle Top Brownies

Chocolate Peanut Butter Pretzel Blondies

Giant Salted Espresso Hot Fudge Cookies

Lastly, if you make these Bake Sale Peanut Butter Oat 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, donโ€™t forget to tag me on Instagram! Looking through the photos of recipes you all have made is my favorite!

Bake Sale Peanut Butter Oat Bars

Bake Sale Peanut Butter Oat Bars | halfbakedharvest.com
3.14 from 29 votes
24 bars
calories 322kcal
Prep20 minutes
Cook20 minutes
Resting Time2 hours
Total2 hours 40 minutes
Chewy, chocolatey, and layered with peanut butter. A nostalgic school lunchroom favorite perfect for fall!
Save this recipe!
Enter your email and we'll send it straight to your inbox. Plus you'll get new recipes from us every week!

Ingredients 

Icing

Instructions 

  • 1. Preheat the oven to 350ยฐ F.ย Line a 9ร—13 inch baking dish or 13x18 inch half sheet pan, with parchment paper.
    2. In a large mixing bowl, beat together the butter, brown sugar, 1 cup of peanut butter, and vanilla until combined. Beat in the eggs. Add the flour, oats, baking soda, and salt.
    3. Press/spread the dough out into the prepared dish. Bake for 18-22 minutes, until just set in the center. Remove from the oven and dollop 1 1/2 cups of peanut butter over the bars, lightly spreading the peanut butter in an even layer. Let cool completely, you can chill in the fridge to speed this up.
    4. Meanwhile, make the icing. In a bowl, whisk together the powdered sugar, cocoa powder, vanilla, and 3 tablespoons of water until smooth. Stir in the melted chocolate. If your icing is too thick, thin with 1-2 tablespoons additional water. Spread the icing over the bars. Let set for 1-ish hourโ€ฆor slice, snack, and enjoy!

Nutrition

Calories: 322kcal

Nutritional information is only an estimate. The accuracy of the nutritional information for any recipe on this site is not guaranteed.

Did you make this recipe? Please rate & comment below.

Meet Tieghan Gerard

I'm Tieghan, the recipes you'll find here are inspired by the people and places I love most. I try to live simply, eat seasonally, and cook with whole foods. My hope is to inspire a love for amazing food, as well as the courage to try something new!

Explore More

3.14 from 29 votes

Add a Comment

Your email address will not be published. Required fields are marked *

Recipe Rating




This site uses Akismet to reduce spam. Learn how your comment data is processed.

87 Comments

  1. Darci says:

    5 stars
    I have made these for bake sales twice & they have been a hit both times!

    1. Tieghan Gerard says:

      Hey Darci,
      Awesome! Love to hear you enjoyed this recipe, I appreciate you making it!

      Have a wonderful day!

  2. Laura says:

    4 stars
    I usually love your recipes. This was very good but was not a personal favorite. My kids did really enjoy it, though they are not picky about sweets :). I think it would benefit from tripling the chocolate on top. I just felt that for the calories and work it was not as good as it looked in the pictures. Consistency also surprised me a bit as I was expecting more of a brownie like chewiness, but it was rather crumbly. The texture was fine, just not what I was expecting.

    1. Tieghan Gerard says:

      Hey Laura,
      Thanks so much for trying this recipe and so many others! So sorry to hear this wasn’t a fave, I appreciate your feedback!

  3. Cheryl Pancino says:

    5 stars
    These bars are fabulous! I love their chewy texture and the chocolate icing is just right. I made them with the extra layer of peanut butter under the icing and without. This will be a regular in my house.

    1. Tieghan Gerard says:

      Hi Cheryl,
      Thanks for testing this recipe out, I’m thrilled it was a success for you. Happy November!๐Ÿ‚๐Ÿ

  4. Maggie says:

    Is there a typo in the ingredients for the icing? 1 1/2 cups of peanut butter?

    1. Tieghan Gerard says:

      Hi Maggie,
      No, there is no typo. Please let me know if you give this recipe a try!

  5. Fran says:

    5 stars
    These are delicious! Made these tonight and we absolutely loved them. Will definitely make them again.

    1. Tieghan Gerard says:

      Hi Fran,
      I really appreciate you making this recipe and reporting back. Thrilled it turned out well! Have the best weekend!

  6. Molly says:

    Is 1 T of vanilla and the 2 oz of chocolate the only liquid with the 2 cups of powdered sugar? Mine needed way more liquid to be able to mix up. Any ideas on what to add to it? Thanks!

    1. Tieghan Gerard says:

      Hi Molly,
      Yes, that is correct. You can add 1-2 tablespoons of water to thin it out. I hope this helps!

      1. Emily says:

        I am SO excited to make these for after school snacks! Do you recommend natural peanut butter for this recipe?

        1. Tieghan Gerard says:

          Hi Emily,
          Yes, that is what I like to use:) I hope you love this recipe!

  7. Jana says:

    5 stars
    These were SO delicious! Not too sweet and so soft and moist. The key is to not over bake. I also added a little bit of peanut butter to the chocolate icing and it made it even better! 10/10 would recommend! Thanks, Tieghan!

    1. Tieghan Gerard says:

      Hey Jana, Thanks so much for making this recipe, I’m so glad to hear it was a hit! Have a great day! xT

  8. Kate says:

    I made a variation of this when I needed to use up a can of pumpmin. Swapped the peanut butter for pumpkin and added a hefty scoop of pumpkin pie spice. So airy and delicious. Iโ€™m sure itโ€™s even better with peanut butter.

    1. Tieghan Gerard says:

      Thanks so much, Kate! So glad this recipe was enjoyed, I appreciate you making it! Happy September:)

  9. Kass says:

    5 stars
    Made these this evening and they were DELICIOUS! I was baking at elevation, in a gas oven, in a half sheet pan so mine were done (middle starting to set) at about 16 minutes. I also used crunchy PB, because thatโ€™s what I had on hand. Everyone loved them. Will make again!

    1. Tieghan Gerard says:

      Hey Kass! Thank you SO much for trying out the recipe! Love to hear you enjoyed these pb bars! Have a great week! ๐Ÿ™‚ xT

  10. April says:

    5 stars
    So good!! Made them for a college tailgate party. They barely made it out of the house because everyone was cutting little pieces the night before! Easy recipe. Came together so quickly. Texture is great. Frosting is so on point! The comments on this recipe are embarrassing.

    1. Tieghan Gerard says:

      Hi April! Thank you so so much! SO glad you loved these PB bars! Thanks for the kind comment ๐Ÿ™‚ xT

  11. Julie says:

    5 stars
    I wanted to eat the entire pan, these were so good! I was hesitant to make them due to the negative reviews, but I thought, how could brown sugar, butter, oats, vanilla, peanut butter, and chocolate go wrong? Just in case, I left out 3/4 c flour (due to concerns in reviews about dryness/ crumbling) and I cooked them 22 min- you want to take them out slightly underdone to keep the moist chewy yum of peanut butter cookie- so even at 22 min it seemed slightly underdone, but was not! I melted chippies with 1/4 c peanut butter for my chocolate top, over the layer of peanut butter, and it was PERFECT. Kids loved them. Thank you IG for telling me I needed to make these today, Perfect back to school treat for kids!

    1. Tieghan Gerard says:

      Hi Julie! So glad you gave them a try and loved them! Your tweaks sound delicious, especially the extra peanut butter in the chocolate topping. Perfect idea for a fun back to school treat! xT