Oat Flour Peanut Butter Cookies

These soft, slightly chewy, lightly salty, and almost melt-in-your-mouth oat flour peanut butter cookies are the peanut butter cookies of my dreams. They taste even better on their second day, and you might want to add a smattering of milk chocolate or dark chocolate chunks to make them even more delicious.

These beauties are unapologetically cookie-there's a lot of dark brown sugar plus a healthy addition of salt to keep things interesting. I'm quite partial to the flourless peanut butter cookies in my cookbook, but when you want a cookie that's a bit more fluffy, as these are, some sort of flour is necessary (you could also make my gluten-free peanut butter cookies that call for a gluten free flour blend). Oat flour works perfectly here, with the bonus that it adds whole grains. Ready to bake? Read on ...

The Best Oat Flour PB Cookies

I could sing the praises of peanut butter all day-from gluten free banana peanut butter cake to gluten free chocolate cake with peanut butter frosting to gluten free peanut butter blossoms, it's safe to say I am a huge fan. I'm also a big proponent of using oat flour when possible (see baking with oat flour for more), and the combo of whole grain, slightly sweet oat flour and peanut butter is a favorite. Here's why you'll love these cookies:

• One bowl. Yes, this cookie dough comes together in one bowl! So, so easy.
• Satisfies that peanut butter craving. What is it about peanut butter that makes it so hard to resist? Add a little brown sugar and salt, and turn it into the best cookie ever.
• Can't tell they're gluten-free. Another reason I love baking with oat flour is that it's almost impossible to tell you're using a gluten-free flour. Cookie recipes are particularly great when made with oat flour, because you can do a direct 1:1 swap of oat flour for all-purpose flour by weight in almost any cookie recipe you can think of. Try it here and see what you think.

Ingredients You'll Need

Make sure to scroll down to my recipe card at the bottom of this post for the full ingredient amounts and instructions!

• Peanut butter - I use the fresh ground peanut butter sold by my local grocery store, but any type of peanut butter will work. Note that if you use sweetened peanut butter the cookies will taste sweeter.
• Butter - I always use unsalted butter brought to room temperature, BUT for a more sweet-salty vibe, go ahead and use salted butter.
• Brown sugar - Either light or dark brown sugar works (I used dark brown sugar).
• Egg - A large or extra-large egg is fine.
• Vanilla - Pure vanilla extract or vanilla bean paste adds a little vanilla undertone.
• Oat flour - Pick up a package of oat flour, or learn how to make oat flour. If you can't have oats, substitute brown rice flour.
• Baking soda
• Salt - I use fine-grain sea salt, and if you have flaky salt, sprinkle a little over the tops of the cookies!

Tips & Substitution Suggestions

• Refrigerate the dough - Make sure to let the dough chill in the fridge; this deepens its flavor and lets the oat flour hydrate. You can prepare the dough up to 2 days before baking and store it in an airtight container in the fridge.
• Slightly underbake - You can adjust the texture of the cookies by making them crisper by baking a bit longer, or softer by underbaking them. I tend to prefer the latter, but it's up to you!
• Reduce the sugar - In my opinion, these cookies are just sweet enough, but you can reduce the sugar to ¾ cup if you want a less-sweet cookie.
• What kind of peanut butter? I always choose a natural peanut butter; I'm lucky to have access to fresh ground peanut butter at my local grocery store. However, you can use any peanut butter in this recipe. If you do use a "natural" peanut butter, make sure to stir in the oil first before adding it to the butter.
• Make them vegan - For an easy vegan batch of cookies, use 1 flax egg for the egg and your favorite non-dairy butter or coconut oil for the butter.
• Naturally sweet - Swap coconut sugar or maple sugar for the brown sugar.
• Add-ins: Try chopped peanuts or almonds, mini or regular chocolate chips, or sprinkle flaky salt across the tops of the cookies just after they come out of the oven.

Serving Options

You can use cookies to make the best ice cream sammies! Try filling them with chocolate sorbet or 1-ingredient banana ice cream for a yummy treat. Crush cookies and use them as a base for a cheesecake or a chocolate cream pie. Or, spread a little Nutella on top and devour. I also love cookies with a big glass of milk or a cup of coffee alongside.

Proper Storage

• Counter - Transfer cooled cookies to an airtight container and store them at room temperature on the counter for up to 5 days.
• Freezer - Place cookies in an airtight container or freezer-safe bag and store them in the freezer for up to 2 months. Thaw the cookies in the fridge before serving.