These peanut butter brownies are a chocolate and peanut butter fan’s dream come true. The rich, dense, chocolate brownie has pockets of peanut butter throughout. These are easy to make, even easier to eat, and great for sharing.

A stack of three brownie butter brownies showing the sides

These decadent peanut butter brownies start with my easy brownie recipe, which is one of my favorite recipes. It’s super easy to make, uses simple ingredients you likely have on hand, and gives you a classic brownie texture. They’re not too dense but not too cakey, either. Plus, you use cocoa powder only, which means there’s no need to get a chocolate bar or bother with melting. They’re so quick, easy, and good that it makes you wonder why you’ve bothered with all that in the past!

They are only made better with the addition of pockets of peanut butter. Creamy peanut butter is swirled over the brownie batter, letting some of it sink into the batter while keeping a nice amount right on top. You really get the best of both worlds in every bite!

Oh, and did I mention that thanks to the oil base, these stay moist for days? No need to worry about them drying out if you bake them a day or two in advance.

Why This Peanut Butter Brownies Recipe Is So Good

Chocolate + peanut butter = perfection. These brownies have just the right balance of both flavors. Neither overpowers the other. And no two flavors go together quite like chocolate and peanut butter, like in my Reese’s peanut butter pie and peanut butter chocolate layer cake.
Fudgy, cakey texture. The base of these peanut butter brownies really walks the line between cakey and fudgy brownies. They’re not too dense or too cake-like. The soft but chewy texture pairs perfectly with the creamy peanut butter on top.
SO easy to make. My absolute favorite thing about these brownies is that they just require a couple of bowls and a whisk. There’s no need to break out the mixer or a bunch of dishes. Since they’re made with cocoa powder, you don’t even have to worry about the extra step of melting chocolate!

Ingredient Notes

These brownies are made with very basic pantry staples, plus cocoa powder and peanut butter. Here’s an overview of everything you need and why; the exact measurements can be found in the recipe card at the end of the post.

Overhead view of ingredients needed to make peanut butter brownies

All-purpose flour – As with any brownie recipe, it’s important to measure the flour correctly to avoid dry brownies. I like to use a kitchen scale, but the spoon and level technique (outlined in this post on how to measure flour), works too.
Cocoa powder – Regular natural unsweetened cocoa powder works great for this recipe. You could try Dutch cocoa powder, but the brownies would probably be more dense.
Baking powder – Be sure to measure accurately here, too. The extra 1/8th teaspoon does make a difference in the texture!
Salt – Brings out the natural flavors already present in the brownies. Without a little salt, the brownies will be bland.
Vegetable oil – I use oil instead of butter in these brownies because the oil creates the best combination of the cakey and fudgy texture. Using butter makes the brownies more dense and they will dry out more quickly.
Sugar – Sweetens the brownies and adds moisture.
Vanilla extract – Helps soften the bitterness of the cocoa powder.
Eggs – Add chewiness to the brownies and helps bind all of the ingredients together.
Creamy peanut butter – Any brand of processed peanut butter works. Avoid natural peanut butter, as the oil tends to separate and it doesn’t have the same smooth, creamy texture.

How To Make Peanut Butter Brownies

When I say these brownies are super quick and easy to make, I mean it! The printable instructions can be found in the recipe card below.

To begin, preheat the oven to 350°F. Grease a square baking pan, line it with parchment paper (leaving overhang on two sides) and then spray the sides with baking spray.

Whisking dry brownie ingredients in a bowl

Combine the dry ingredients in a bowl.

In another bowl, mix the oil, sugar, and vanilla until well combined.

Add the eggs to the oil mixture. Mix until well combined.

Add the dry ingredients to the wet ingredients. Mix until combined, but don’t over mix.

Spread the batter evenly into the pan.

Dollops of peanut butter on brownie batter in a square pan

Drop spoonfuls of peanut butter on top.

Peanut butter swirled into brownie batter

Run a knife through the peanut butter to swirl it into the brownie batter.

Overhead view of a pan of baked peanut butter brownies

Bake for 25-30 minutes, until a toothpick comes out with just a few crumbs.

Let the brownies cool completely in the pan. Then, use the parchment paper to remove them from the pan. Cut into bars and enjoy!

Angled overhead view of peanut butter brownies stacked on parchment paper

Tips for the Best Brownies

Line & grease the pan. To make things easier when you’re ready to enjoy the brownies, line the pan with parchment paper and leave overhang on two sides. I also grease the sides so that the edges don’t stick when I try to lift it out of the pan.
Don’t over-mix the batter. After combining the wet and dry ingredients, mix just until the dry ingredients are combined with no streaks of flour. Mixing too much can lead to dense, tough brownies.
Swirl gently. When swirling the peanut butter and brownie mix, try to do so with some intention. If you over-swirl them, they’ll eventually just mix in together and you won’t have distinct pockets of peanut butter on top. It’s easiest if the spoonfuls of peanut butter are evenly placed all over the batter.
Moist crumbs are okay. Every oven is different, so check your peanut butter brownies right at the 25 minute mark. A toothpick should come out with a few moist crumbs but no wet batter. It’s easiest to test a spot without peanut butter.
Cool in the pan. The final step to soft, chewy peanut butter brownies is to let them cool completely in the pan before slicing, so they aren’t too soft and fall apart.

A peanut butter brownie with a bite missing

Proper Storage

Room temperature: These peanut butter brownies stay fresh for 5-7 days when stored at room temperature. Just keep them in an airtight container.
Fridge: For slightly longer storage, they can also be placed in an airtight container in the fridge for 7-10 days.
Freezer: To freeze, wrap each brownie in plastic wrap, then place them in a freezer-safe container. Freeze for up to 3 months. Thaw in the fridge or on the counter.