Filed under: Cookies / Drop Cookies
January 19, 2024

Oat Flour Peanut Butter Cookies

Chewy, crinkle peanut butter cookies gluten free and made with oat flour!

4.96 from 22 votes
Yield: 14 large cookies
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Oat Flour Peanut Butter Cookies

These started with this small batch peanut butter cookie recipe, but since we are making a full batch I used the whole egg rather than just the yolk. And since making these thick and chunky peanut butter cookies, I’ve been rather drawn to using chunky peanut butter for those added specks of crunchy nuts. Lastly, of course, we’re making these with oat flour instead of all purpose. 

 

The reason for this is well, I just love oat flour in cookies, brownies, muffins and blondies. But especially in cookies because unlike other ‘alternative’ flours, oat flour behaves quite similarly to all purpose yet it adds a lovely oaty flavor and it makes the cookies extra chewy. This chewiness is what I just adore here. 

These bake up into these gorgeous cracked cookies with crinkles all over, kind of like a molasses cookie look, but with the dual flavor of hearty oats and salty peanut butter. 

 

Recipe Ingredients 

Butter: Where I usually say you can use salted or unsalted, here I have a preference for unsalted because we’re already getting added salt from the peanut butter. That said, if salted is all you have and you have a ‘saltier’ tooth, you can use it but omit the added salt altogether. 

 

Sugar: Both fine granulated and brown sugar. The brown can be light or dark. If it’s dark the cookies might spread a bit more than what you see in the photos. 

 

Peanut Butter: Use a generic brand (not homemade) that does not separate when left in the jar. I use JIF natural. You can use creamy or crunchy here. 

 

Salt: fine sea salt, NOT table salt. 

 

Egg: Just one large egg. I haven’t yet experimented making these egg-free but if I were to, I’d use 1 tablespoon ground flaxseed and 1 tablespoon of water. 

 

Vanilla: Pure vanilla extract or vanilla bean paste. 

 

Leavening: Both baking soda and powder  here, one to help them spread and one to help them rise up, then crack. Check the dates on the jars, make sure it’s still fresh! 

 

Oat flour: I use store-bought, either Arrowhead Mills, Bob’s Red Mill or (the most affordable and just as great) Anthony’s. I have never had success making my own oat flour, perhaps because I have a standard food processor that cannot ‘mill’ it fine enough. 

How to make Oat Flour PB Cookies 

Start by partially melting the butter. You can do this in a microwave for 1 – 1.5 minutes or over the stove. Stop when the butter is about two thirds melted and can be ‘creamed’ 

Add the flavorings and whisk into the butter. Adding them to the fat portion of the dough brings the flavors out more 

Pour in the sugars and whisk, very well. You’ll see the mixture start out grainy and separated and as you whisk it will turn shiny and cohesive 

Measure in the peanut butter (this is one of those instances where a scale is wonderful because you won’t have to deal with scraping it out of a measuring cup!) and whisk it in.

Crack in the egg and whisk very well 

Add the oat flour, baking powder and soda and switch to a rubber spatula. Stir until combined 

Uncovered, let the dough chill in the fridge for one hour (if you need to leave it longer, cover it) 

Preheat the oven and prep two cookie sheets by greasing them then lining them with parchment paper (the grease keeps the parchment paper in place) 

Portion the cookies into 1.5 tablespoons to 2 tablespoons of dough each. 

If you like, you can roll them in granulated sugar before baking (I add a pinch of fine sea salt to the sugar and whisk before rolling so you get a nice sweet/salty flavor) 


In the oven the cookies will spread quickly, then puff up and crack. Once they have done so and have golden-ish edges, take them out. They’ll cool for about ten minutes on the pan then you can eat them =) 

 

Make Ahead Tips 

The dough needs an hour to chill (uncovered) in the fridge before baking. But if you like, you can leave it overnight – just cover it in plastic wrap to seal. 

If you’d like to scoop the cookies and store them in the freezer, make the dough then chill the dough for an hour. Portion the cookies onto a parchment lined plate or tray and freeze them until solid, about 15 minutes. Then transfer to a ziplock bag to freeze. 

Bring the cookie balls to room temperature, then bake as directed.

 

Chocolate Chip Oat PB Cookies 

You’re always welcome to add chocolate chips or chocolate chunks! Bear in mind that chunks, which melt beautifully in the oven unlike chocolate chips, will push the cookies to spread even more. 

 

Oat Flour Peanut Butter Cookie Recipe 



Oat Flour Peanut Butter Cookies

Chewy, crinkle peanut butter cookies gluten free and made with oat flour!
Prep Time: 15 minutes
Cook Time: 12 minutes
Chill Time: 1 hour
Yields: 14 large cookies
4.96 from 22 votes

Ingredients

  • 113 g or ½ cup unsalted butter
  • 100 g or ½ cup granulated sugar
  • 100 g or ½ cup brown sugar
  • ½ tsp fine sea salt
  • 1-2 teaspoons pure vanilla extract
  • 1 large egg
  • 165 g or ⅔ cup crunchy peanut butter generic brand that does not separate
  • 1 teaspoon baking soda
  • ½ tsp baking powder
  • 195g or 1 ½ cups oat flour

Method

  • In a heatproof bowl, melt the butter in the microwave until it’s almost but not fully melted (about 1 minute at 100% power - if the butter was very cold you might need another 30-45 seconds).
  • Add the sugars and the vanilla and salt and whisk very vigorously, until the mixture starts to turn cohesive and shiny.
  • Add the peanut butter and whisk to combine.
  • Add the egg and whisk very well.
  • Fold in the oat flour, baking powder and soda and stir until there’s no visible flour bits.
  • Set the bowl in the fridge, uncovered for one hour. If you need to leave it longer, cover with plastic wrap to seal.
  • Preheat the oven to 350 F. Line two baking sheets with parchment paper.
  • Scoop the dough into 1.5 - 2 tablespoons of dough per cookie, leaving at least an inch diameter of space around each cookie as they will spread.
  • Bake for 10-12 minutes, until the edges are slightly golden and the cookies have puffed up and cracked.
  • Store cookies in an airtight container at room temperature.

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Recipe Reviews




  1. 5 stars
    I’ve made these so many times and everyone loves them. I’ve followed the recipe exactly with weights the last few times, and noticed the dough was really dry and needed a little squish to spread. I just made these again but only had around 170g of oat flour, dough looked exactly like the pictures and spread beautifully. I use the Bob’s oat flour so I wonder if this varies by brand or if there was something I overlooked. I will also say PB brand and type absolutely does matter, Skippy & Whole Foods crunchy was great, Skippy creamy didn’t quite come together the same way. Really enjoy your recipes! 🙂

  2. Delicious! I use pure monk fruit extract and only 2tbs of sugar- they’re quite crumbly though but my husband loves them

  3. Way too sweet.
    Love the oat flour which I made in a blender.
    Can I substitute ripe banana for the sugar?

  4. I substituted 1 cup of oats and used half cup of oat flour instead of 1 1/2 cups of oat flour alone.
    The dough was pretty thin so I added another 1/2 cup of oat flour. It was still a pretty liquidy dough so the cookies spread quite a bit. They were very thin when baked but tasty.

  5. I followed this recipe exactly measured everything on a scale and my cookies did not spread. After baking they were still in ball form. I used a 1.5 tablespoon scoop.

  6. 5 stars
    Delicious! especially with the sugar/salt dip before baking. I had to use coconut sugar in place of brown sugar. I also ground oats in a nutribullet for the oat flour. I made this all in a medium sauce pan which was fast and easy. Thanks for this recipe. Received lots of compliments.

  7. 5 stars
    These are a really, really good peanut butter cookie! I followed the weight measurements and divided the dough into 14 cookies – this makes them large, yes, but try it (aka trust Sam). The texture and crunchy edge to chewy center ratio is perfect when you make them this size! I really don’t care for the texture of the “three ingredient peanut butter cookie,” and I love the slight nuance in flavor that oat flour gives, so I’ll definitely be making these again. Plus, my family loved them, and they’re typically resistant to ANYYY deviation from classic recipes/ingredients, so that was high praise.

  8. 4 stars
    Recipe measurements and directions were accurate and straight forward. I’m not sure if the final product tasted or looked different enough from a standard three ingredient easy peanut butter cookie to justify the extra ingredients.

  9. 5 stars
    i veganized these with a flax egg (1 tbsp ground flax, 3 tbsp water) and olive oil instead of butter (80g) and they turned out super good.

  10. 5 stars
    Brilliant, love the way these turned out. They look just like an Anzac Biscuit, nice and flat. I must admit that I didn’t wait 1hr to cook these as 25min in the fridge was all we could wait. I also processed my quick oats in the food processor instead of using oat flour and added 1/2cup of chocolate chips. My daughter who is Gluten free loved them.

  11. 5 stars
    I made these with the weighted (g) measurements and they came out perfectly. I also did a little recipe testing. I spooned and leveled 1.5 c of oat flour that the recipe calls for and it weighed 168 g. The recipe says it is 198 g, which was a heaping 1/4 c difference. I also checked on King Arthur’s site and they say 1.5 c of oat flour is 138 g which is a 57 g difference with what this recipe states. The point is, if you don’t use the weighted measurements with the recipe I wouldn’t expect the same results. The other recipe test I did was I tried to make this with AP flour. I weighed the oat flour at 195 g and spooned it into a measuring cup. It was level with the 2 c line. So I spooned 2 c of AP flour into the measuring cup. Then I weighed it. It was 225 g of AP flour. I used that for the recipe because it appeared to at least be the volume conversion. Outcome……not as much flavor, slightly dry and crumbly, and not as flat. I might try it again with 1.5 c of AP flour instead. Otherwise, recipe left alone made with gram measurements is perfect.

  12. 5 stars
    My new favorite peanut butter cookies!
    The chewiness is unmatched by any other cookie I’ve made; it was my first time using oat flour. I found 13 minutes worked best in my oven. Loved that I didn’t have to break out the mixer for them too!

  13. Can we substitute oat flour with 1:1 gluten free flour or almond flour? What would you suggest as a good substitute for oat flour? Thanks!

  14. Potentially really dumb question ????. If I don’t have flour, could I blend oatmeal until it’s super fine in my vitamix? ????

    • So i’ve never had success doing this but others have done it with my oat flour blondie/brownie recipe and it worked for them. That said there’s more liquid in those so I see it being less of an issue. I guess my answer is, I don’t know tbh!

  15. will this recipe work with rye and whole wheat flour? i don’t have oat flour in hand but definitely want to try. lookin so good as always!

    • I am not sure about rye but I would definitely say no to the whole wheat flour; the amount of gluten in the whole wheat will make for a tough dry cookie and they won’t spread properly

  16. Hi, I just have a question: the only peanut butter I use is natural, would that totally ruin the recipe or is it worth giving it a try?

    • Is it a generic brand that’s ‘natural’? I used Jiff Natural for these and it worked great. If it’s pure peanut paste (like no added ingredients) I suspect it will alter the texture of the cookie.

  17. I love the sound of these peanut butter cookies and have bought oat flour and will make them this weekend. You are the queen of browning butter, so many of your recipes call for that, which really elevates them to another level of deliciousness. I have not seen it in this recipe which surprised me, any reason and do you think it would be ok to do.
    I’m on the browned butter band wagon now, you have converted me!

    • Hi! I love that you are just as big of a fan of brown butter as I am ;p
      You pose a good question, my goal with this recipe was to create a peanut butter cookie that was big, crinkly and super chewy and I knew oat flour would get us there. When it comes to browning butter, other adjustments have to be made: you need to start with more than the recipe calls for and you have to makeup for the lost moisture (I sometimes do this with sour cream). I suppose the answer is, I just didn’t think of it for these! You can try it but I wouldn’t expect the same result or texture (although the flavor might be improved 😉 )

  18. Love! I love this one-bowl stir-it-all-together Peanut Butter Cookie! Sam has turned me into an oat flour convert and this cookie is probably my favorite!