Peanut Butter Oat Cookies
These peanut butter oatmeal cookies are 100% delicious. Plus, they're gluten free and easy to make in just one bowl. Meet your new favorite cookie recipe!
Updated by Kathryne Taylor on September 19, 2024
I’d like to introduce you to my new favorite cookies. This peanut butter oatmeal cookie recipe yields cookies that are tender on the inside, chewy around the middle, and just barely crisp around the edges.
These cookies are loaded with pure peanut butter flavor. They’re sweet, but not cloyingly so. If you’re a fan of my monster cookie recipe, you’ll enjoy these as well. I can vouch that they’ll be a hit with your family, friends, kids and coworkers.
Oats make these cookies more hearty than most. In fact, oats are the only structure this flourless cookie recipe needs. As long as your oats are certified gluten free, these cookies will be, too.
These cookies are easy to make, too. You don’t need to soften your butter first (just melt it). You don’t need to pull out a heavy stand mixer (your hand mixer or some elbow grease will work great). And, you’ll only need one mixing bowl. Winning!
More than any other merit, though, these peanut butter cookies are delicious. They’re cookies and that’s what cookies should be, right?
Peanut Butter Oatmeal Cookie Ingredients
This recipe is quite versatile. You’ll notice that different amounts are offered for some of the alternative options. That’s because they vary by volume (and make my job more difficult, but who can complain about extra cookies?).
Peanut Butter
As it turns out, creamy or chunky peanut butters work. I generally buy “natural” peanut butters, and this recipe has worked with all of them. You can even make your own peanut butter for freshly roasted peanut flavor.
Coconut sugar or brown sugar
Coconut sugar is a less refined sugar with a few trace nutrients, and I always try to work with natural sweeteners when possible. Brown sugar works well if that’s what you have on hand.
Coconut oil or butter
Either way, melt it before using. I can’t really taste the coconut oil, but it does make the cookies taste more interesting in a hard-to-put-your-finger-on kind of way. That’s why I chose to list coconut oil first. If you want your cookies to be dairy free, use coconut oil.
Eggs
Eggs act as a binding ingredient and a leavener, which means that they help the cookies rise. Eggs are essential if you want your cookies to turn out like mine. That said, I’ve shared some notes from readers about using flax eggs as an alternative in the recipe notes.
Baking soda
Baking soda is another leavener that helps your cookies bake up nice and fluffy. Don’t substitute baking powder; they behave differently. Always, always, always use the leavener specified in the recipe.
Quick-cooking or old-fashioned oats
Quick oats disappear more into the cookies, creating a more uniform texture. I prefer quick-cooking oats, so that’s what you’ll see in the photos. Old-fashioned oats offer a more hearty and discernible texture.
Peanut Butter Oatmeal Cookie Variations
Substitute other nut butters.
I love how these cookies turn out with peanut butter, but they’ll also work with almond butter or sunflower seed butter.
Stir in some extras.
You can add up to 1 1/2 cups chocolate chips, chopped nuts, raisins or dried fruit.
Make bigger cookies.
This recipe yields around 27 medium cookies (about 3 inches across). If you double the size of each cookie to use 1/4 cup of dough each, you’ll end up with 13 to 14 large cookies instead (about 4.5 inches wide). The large cookies will require somewhere between 8 to 11 minutes in the oven.
Please let me know how your cookies turn out in the comments! I love hearing from you and appreciate your feedback.
Craving more cookies and treats? Check these out:
- Chocolate Peanut Butter Crispy Bars
- Monster Cookies
- Spiced Oatmeal Cookies
- Coffee Chocolate Chip Blondies
- Vegan Chocolate Chip Cookies
Peanut Butter Oatmeal Cookies
These peanut butter oatmeal cookies are 100% delicious. Plus, they’re gluten free and easy to make in just one bowl. Meet your new favorite peanut butter cookie recipe! Recipe yields about 27 cookies.
Ingredients
- 1 ½ cups creamy or chunky peanut butter (that’s one full 16-ounce jar minus ¼ cup)
- 2 ½ cups packed coconut sugar or 2 cups lightly packed brown sugar
- ⅓ cup melted coconut oil or 5 tablespoons melted butter
- 3 large eggs
- 2 teaspoons baking soda
- 2 teaspoons vanilla extract
- 2 ½ cups quick-cooking oats or 2 ¾ cups old-fashioned oats (certified gluten-free if necessary)
- Optional: flaky sea salt, for sprinkling
Instructions
- Preheat the oven to 350 degrees Fahrenheit. Line tw0 large, rimmed baking sheets with parchment paper or silicone mats for easy clean-up.
- In a large mixing bowl, combine the peanut butter with the sugar and coconut oil. Use an electric mixer or a large spoon to mix until well combined. Add the eggs, baking soda and vanilla, and mix well. Add the oats and mix until they’re evenly incorporated.
- Drop 2 tablespoons of dough per cookie onto the prepared baking sheets. These cookies spread while baking, so leave a couple of inches around each one. Gently shape them into a more rounded mound and press down lightly so they’re no taller than 1 inch.
- Bake 8 to 10 minutes, until they’re just starting to turn golden around the edges. Do not overbake. They will flatten more as they cool. Let the cookies cool for 10 minutes before transferring them to a cooling rack. In the meantime, bake your next round of cookies, and so on.
- If desired, sprinkle the cookies lightly with flaky sea salt. Let them cool completely before storing them in an airtight container. Cookies will keep well for several days at room temperature.
Notes
Nutrition
The information shown is an estimate provided by an online nutrition calculator. It should not be considered a substitute for a professional nutritionist’s advice. See our full nutrition disclosure here.
Hello Kate,
I enjoy many of your recipes. Your Green Beans Amandine are a fave. Want to try these PB cookies. Conflicting info though – a cup and a half should be 12 oz, but a 16 oz jar minus 1/4 cup would be 14 oz…I’m thinking I’ll go with 14 but will watch for your clarification. Thank you!
Hi Rae, because peanut butter is dense, its weight in ounces is different from its volume in ounces (cups are volume). 1 cup of peanut butter is 9 ounces b y weight.
Oh, that is so helpful! I would never have guessed. That could be a reason I’m getting some peanut butter recipes wrong. Thank you so much.
Hi Rae, ounces can be confusing, because it is used to describe both volume and weight! For solids, you can usually assume it means weight, and for liquid, volume.
Excellent. Thanks!