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After nearly a year of testing, I’m officially ready to share my ‘better than the Lunch Lady’s’ Peanut Butter Bars! Capped with chocolate frosting and full of oats + peanut butter, these baked bars simply cannot be beat!
Peanut Butter Oatmeal Bars
Making and eating these peanut butter bars is an annual top 3 back to school experience for me! Oozing nostalgia, this take on lunch lady peanut butter bars is an absolute touchdown! Tender bars, chock full of peanut butter and oats and topped with a delectable chocolate frosting. Um, hello. Yes, I’ll eat the whole pan, thank you.
While I have a soft spot for no-bake peanut butter bars, this oven masterpiece is ridiculously soft, slightly gooey and exactly what I want a classic peanut butter bar to be.
What’s In Peanut Butter Bars Recipe?
- Salted Butter, softened – If you don’ have salted butter and only have unsalted on hand, that is fine! Just add an extra pinch of salt to the recipe to make up for it.
- Peanut Butter – I use creamy peanut butter but crunchy would definitely work too. I have not tested this recipe with natural peanut butters so I am unsure of how that could change the outcome of the recipe!
- Granulated Sugar
- Brown Sugar – This helps give the bars a nice rich & warm depth of flavor.
- Eggs
- Vanilla Extract
- All-Purpose Flour
- Old Fashioned Oats: I haven’t tested this recipe using quick oats so I would strongly suggest using old fashioned oats for this recipe.
- Salt
- Baking Soda
Chocolate Icing
- Salted Butter
- Cocoa Powder – We are looking for unsweetened cocoa powder here.
- Milk – I just use what I have on hand, sometimes that is skim milk and sometimes it is whole milk! It all will be sufficient for this recipe.
- Powdered Sugar
- Vanilla
How to Make Peanut Butter Bars
- Prep by preheating the oven to 350°F and greasing a 9×13 pan.
- With an electric hand mixer or a stand mixer, cream together the peanut butter, butter and sugars until light and fluffy.
- Add in the eggs and vanilla, mixing until just combined.
- To the mixture, add in the flour, old fashioned oats, salt and baking soda.
- Mix until a slightly sticky dough forms.
- Next, spread and press the finished dough into the bottom of your greased pan.
- Place your pan in the oven and bake at 350°F for 18-20 minutes.
- Remove your peanut butter bars from the oven when the edges are starting to turn golden and begin making the frosting.
- To make the frosting, melt the butter, cocoa powder and milk in a medium saucepan over medium heat. Bring the mixture to a soft boil.
- Once boiling, remove the pot from the heat and whisk in the powdered sugar and vanilla until smooth.
- Let the icing cool for 10 minutes.
- After it has cooled, stir the icing to break up the crusting on top and then pour over the peanut butter bars.
- Allow the bars + frosting to cool completely before cutting. (You can put it in the fridge to speed up the process, if desired.) Enjoy!
How to store Peanut butter bars?
Store your peanut butter chocolate bars in an airtight container at room temperature for up to a 3 days. These also freeze really well up to 3 months. Just let them thaw on the counter when you’re ready to serve.
Can I make peanut butter bars dairy free?
Absolutely! With dairy free chocolate chips, vegan butter and a dairy free milk, this recipe can easily be made dairy free and still turn out delicious!
More Classic Desserts to Devour!
- Puppy Chow
- Reese’s Fudge
- Microwave Peanut Brittle
- No Bake Cheesecake
- Cookie Dough Bites
- Oreo Pie
- Rice Krispie Treats
- Buckeye Balls
Peanut Butter Chocolate Bars
Ingredients
Peanut Butter cookie Layer
- 1/2 cup (111g) salted butter
- 1 cup (246g) peanut butter
- 1/2 cup (115g) granulated sugar
- 1/2 cup (123g) brown sugar
- 2 eggs
- 2 tsp vanilla
- 1 1/2 cups (228g) all-purpose flour
- 1 cup (100g) old fashioned oats
- 1/2 tsp salt
- 1 tsp baking soda
Chocolate Icing
- 1/2 cup (111g) salted butter
- 4 tbsp cocoa powder
- 6 tbsp milk
- 1 lb powdered sugar
- 1 tsp vanilla
Instructions
- Preheat oven to 350°.
- Cream together peanut butter, butter and sugars until light and fluffy with either a stand mixer or electric hand mixer.
- Add in the eggs and vanilla, mix until just combined.
- Add in the flour, old fashioned oats, salt and baking soda.
- Mix until the dough forms. Dough will be slightly sticky.
- Spread and press the dough into the bottom of a greased 9×13 pan.
- Bake at 350° for 18-20 minutes.
- Once the peanut butter bars come out of the oven, make the frosting.
- To make the frosting, melt the butter, cocoa powder and milk in a medium saucepan pan over medium heat. Bring to a soft boil.
- Once boiling, remove from heat and whisk in the powdered sugar and vanilla.
- Let the icing cool for 10 minutes. Stir the icing to break up the crusting on top and then pour over the peanut butter bars.
- Allow to cool completely before cutting. (You can put it in fridge to speed up the process, if desired.)
I was very intrigued when I saw this recipe. Most peanut butter bars use Graham cracker crumbs which I hate so I was happy when I saw this recipe did not. These were beyond good. So full of flavour. The only thing I might do is process the oatmeal so it is just a bit finer in the batter. No matter what I will definitely make them again. So happy I found Karli.
OMG I’m such a sucker for any dessert with PB and chocolate but I’m not usually blown away. These bars are PERFECT. I did a full recipe in a 9×9 pan so they were so thick and the frosting was about as thick as the bars. I literally cleared them out so fast with my husband. The frosting is addicting. Seriously, so freaking good. Thanks for the recipe Karli! I will definitely be making these again soon. Also – I’ve never written a recipie review, it was just that good.
Thank you so much for including the weights for this recipe. I wish all your recipes included them. These came out so good. My family loved them and brought back memories of my childhood.
I made the peanut butter cookie bar and I’m here to tell you it’s easy it tastes wonderful. My husband about passed out he loved it so much. Thanks Karlie another success.
Delicious! Easy to make, well described directions.
This has to be one of the best desserts I’ve ever made! I made them for Mother’s Day and now I’m making them for Father’s Day. My dad always tells me I did a good job on desserts, but you can tell when he’s a big fan of something. When he grabbed his third bar, I knew I had found a new go-to dessert for family gatherings! We are egg-free and these were easy to sub with flax eggs, and they were still amazing.
I’ve been wanting something easy with peanut butter and chocolate so these were a perfect fit. They came together so quickly and are so good! They’re dangerous!
Could almond milk work in place of milk
Hi! I haven’t tried this recipe with almond milk, but it should work! Let me know if you give it a try.
These are Sooo good. As a major Peanut Butter and Chocolate fan, these are a perfect dessert!
10/10 for the frosting. It’s delicious. However, the bars are not the traditional lunch lady bar texture I like. They are thicker and more like a quick bread texture. Not my favorite.