Soft and Chewy 30 Minute Peanut Butter Oatmeal Cookies

Hi hi! I am just popping in to share this Peanut Butter Oatmeal Cookie recipe with you! I developed these when I went down an Oatmeal Cookie recipe rabbithole, which started with my Oatmeal Chocolate Chip Cookie recipe. It was such a good base recipe that I couldn't help myself and had to add in some peanut butter, which was a very good idea.

These peanut butter oatmeal cookies are soft, chewy, and packed full of flavour. They start with a brown butter base, then we add toasted oats, loads of peanut butter, and malted milk powder. There is zero chill time so you can have them ready to go in about 30 minutes!

I love a large cookie so I made them huge, but you can easily scale back if you need! They keep for up to a week in an airtight container. Promise you'll love them. If you're after a raisin situation, check out my Oatmeal Raisin Cookies too which were also part of the oatmeal cookie rabbithole!

My Best Peanut Butter Oatmeal Cookies

There are a few things that make these, to me, the ultimate peanut butter oatmeal cookie:

• Soft and Chewy. I wanted a cookie that was on the thicker side, but super soft and chewy. We got there by playing around with the sugar ratios, and adding enough butter so that they spread nicely without getting too thin.
• Brown Butter. I put brown butter in so many things. It's just the best, it gives the most amazing flavour to recipes, especially cookies. If you want more recipes using it, I have lots of brown butter recipes for you!
• Toasted Oats. I used this technique in my Oatmeal Chocolate chip cookie recipe and loved how it gave the cookies texture, so I used it again for the peanut butter oatmeal. You don't have to toast them, but it's worth it, promise.
• Malted Milk. Malted milk is best friends with peanut butter and brown butter. This is an optional ingredient and if you don't have it you can leave it out as it is a flavour enhancer rather than a thickener, but it's so good!

What is the best Peanut Butter to use for Peanut Butter Oatmeal Cookies?

I prefer a 'creamy' style peanut butter - not natural peanut butter. Creamy peanut butter has been mixed until it has emulsified, which means that there is no separation of the oil and the rest of the peanut butter. Something like Jif or Skippy works - in NZ I use the Pam's one usually.

If it is super cold, your peanut butter might be a tiny bit solid, just pop it in the microwave for 5-10 seconds until it softens. I was able to mix it in just using a whisk into the wet ingredients.

I haven't tried crunchy peanut butter but it should work! If you use peanut butter without any added salt you may have to add some salt to the recipe.

Cookies with malted milk powder

Malted milk powder is a milk powder based product with a few other ingredients added too - it was originally formulated to help babies with digestion. It works particularly well in this recipe as it goes so well with the peanut butter.

You can get malted milk powder online - in NZ I use Horlicks from the supermarket. It tastes slightly different but you get the same outcome - very delicious cookies.

If you do not have malted milk powder on hand you can just omit it from the recipe - it is a flavour enhancer and doesn't change the texture of the recipe so you can just leave it out.

Toasted Oats

This is another optional step - toasting the oats. This just gives them a bit more of a toasty flavour, adding amazing depth into the peanut butter oatmeal cookie. It only takes about 10 minutes - I like to do it while I brown the butter so that they can cool while I do the first part of making the peanut butter oatmeal cookie batter.

If you are wondering what the best sort of oats are to use in Oatmeal cookies - I like Old Fashioned Oats. These are the ones that are just squished regular oats - so not a quick cooking oat or a rolled oat. They provide the best texture in my opinion.

I haven't tried them with quick oats or rolled oats sorry - I would stay away from quick cooking if I were you. They will get really gluggy.

How to freeze Peanut Butter Oatmeal Cookies

There are two ways of going about this:

• Freeze the baked cookies. Once the cookies are totally cool, freeze in an airtight container for up to a few months. Defrost at room temperature - they will benefit from a little refresh in the microwave before you eat them.
• Freeze the cookie dough (my preferred method). Place the dough on a parchment paper lined baking sheet and freeze until solid, then transfer to an airtight container. When you bake from frozen, drop the oven temperature to 325°f / 160°c and add a few minutes onto the bake time.

For all my tips and tricks on freezing cookie dough and cookies, check out my post: How to freeze cookie dough and bake from frozen

How to store Peanut Butter Oatmeal Cookies

Store your peanut butter oatmeal cookies in an airtight container for up to a week. They are best in the first few days, but they keep super well! I keep mine at room temperature.

Recipe Development for Peanut Butter Oatmeal Cookies

The recipe development for this oatmeal cookie series wasn't too tricky once I nailed down my oatmeal chocolate chip cookie. I started with that recipe as the base and made a few changes:

• Removed the chocolate. Obvious step.
• Kept the brown butter. However, I removed adding in the milk powder like you do in the chocolate chip cookies. Because of the peanut butter, the brown butter, toasted oats, and malted milk powder already do a ton of flavour work.
• Played around with sugar ratios. Initially when I made these, I used the same ratios as the chocolate chip oatmeal recipe, but changed to have a higher ratio of white sugar to give spread and chew.
• Spread. The initial test didn't spread as much as I would have liked - they baked up as rocks. They were still delicious but I knew something needed to change, so I reduced the amount of peanut butter (the original test had 200g), dropped the amount of flour I was using, and increased the oats in the recipe. This, combined with changing the ratio of white to brown sugar, sorted it out straight away and gave me perfect, soft and chewy peanut butter oatmeal cookies.

Frequently Asked Questions

What tools and equipment do you use?
You can find a full list of the tools and equipment I use on my products page

Can I add mix-ins?

I haven't tried it, but adding in chocolate chips or toasted nuts would proabably work super well. I would add no more than 150g of mix-ins. It may change how they bake up in terms of thickness but should be fine!