Peanut Butter Brownies start with a fudgy brownie recipe that is filled with a layer of peanut butter in the middle then more peanut butter swirled on top. Your peanut butter friends will love this brownie recipe! Step-by-step photos help you make these pb brownies!

I don't know about you but I go through phases with peanut butter some years I cannot get enough peanut butter. This is one of those years, from my chocolate peanut butter protein shake, to my apple slices with peanut butter, to chicken satay with peanut sauce, I cannot stop! One thing I never get sick of is chocolate and peanut butter together.
I made these peanut butter brownies because as much as I love my peanut butter cup brownies the peanut butter doesn't punch you in the face. Don't get me wrong it's a great recipe but if you're looking for a full-on peanut butter punch these are the brownies you want. It took me a few times to get the recipe just right, but now I love it, and I hope you do too.
Other peanut butter brownie recipes sometimes call for making a peanut buter filling with powdered sugar, I wanted an easy and quick recipe that was just true to peanut butter so for the filling in these brownies all you need is peanut butter. I do suggest using a non-natural type peanut butter- I love to use Jif and Skippy for baking.
You will also see there is peanut butter not only on top of the brownie but also inside.
Let's get to the recipe
Ingredients
Here are the ingredients you'll need for the recipe.
- Water. Good old water, tap is fine!
- Unsalted Butter. Just a little of butter is used for flavor, we then use oil for the rest of the fat.
- Granulated Sugar. We're going to cook the sugar so it melts and provides that glorious crinkly brownie top.
- Cocoa Powder. I prefer the flavor of Dutch-process cocoa, I use Bensdorp Dutch Cocoa Powder.
- Vegetable Oil. Oil provides so much moisture to the brownies.
- Vanilla Extract. Use the real stuff, no imitation here!
- Eggs. We'll use one whole egg and one egg yolk, the extra yolk provides richness and chew to the brownies.
- Baking Powder. Just a little helps give the brownies a little lift.
- Salt. Don't skip it, trust me!
- Cornstarch. Also known as cornflour this ingredient helps tenderize the brownies and give them a softer texture.
- Flour. Just good old all-purpose or plain flour is needed, when you mix the flour in be sure not to overmix!!
- Creamy Peanut Butter. For baking, I prefer brands like Jif or Skippy and save the natural peanut butter for snacks.
Adding a handful of semi-sweet or dark chocolate chips would be fabulous too!
For another nutty dessert check out my almond flour brownies, pistachio cookies or my Reese's smores bars.
Instructions
Preheat your oven to 350F/180C and line a 9X9 or 8X8 square pan with foil and grease heavily. The foil overhang will help you easily pull the brownies out of the pan.
In a large pot add the water, butter, sugar, and cocoa powder.
Cook on low- medium heat for 2-3 minutes, whisking until it is all combined together.
Take off of the heat then add the vegetable oil and vanilla extract.
Let mixture sit for 5 minutes then add the egg and egg yolk. Whisk to combine.
Add the baking soda, salt, cornstarch, and mix to combine.
Gently add the flour by using a spatula to fold in until just combined. Do not over mix, this will affect the end product.
Now we are going to take ⅔rds of the batter pour batter into the prepared pan and use an angled spatula to spread it out, scoop 4oz (½ Cup) of the peanut butter on top of the batter and use an angled spatula to gently spread it into one even layer, as best as you can. Pour the remaining brownie batter on top and then place the remaining peanut butter in chunks then use a butter knife to gently swirl up and down then across.
Make sure you do not overmix or you won't have the pretty peanut butter swirl.
Bake 25-35 minutes.
Everyone’s oven is different, for me, the brownies always bake within 29-31 minutes, but I would start checking at 25 minutes for your oven. Don't overbake the brownies. You want a toothpick in the center to come out with moist crumbs, not completely dry. Place the pan on a wire rack to cool completely before cutting.
Store in an air-tight container on the counter for up to 4 days.
How to freeze
You can totally freeze peanut butter swirled brownies. Let the brownies cool completely then store in a freezer-safe container. Let thaw at room temperature for 30-60 minutes depending on the size of your brownies.
Ideally brownies shouldn't freeze for longer than 3 months.
Can you double
You can easily double the recipe, just bake in 9X13 inch pan I would start checking the brownies at 31 minutes and gauge how much longer- 5 more minutes..etc. You want a toothpick inserted in the center to come out with moist crumbs no wet batter.
More Brownie Recipes
★★★★★ Please let me know if you make this recipe by leaving a star rating and comment below!
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Peanut Butter Brownies
Peanut Butter Brownies start with a thick and chewy brownie recipe that is filled with a layer of peanut butter in the middle then more peanut butter swirled on top. Your peanut butter friends will love this brownie recipe! Step-by-step photos help you make these pb brownies!
- Total Time: 50 minutes
- Yield: 16 1x
Ingredients
- 2oz (¼ Cup) Water
- 1oz (2 Tbsp) Unsalted Butter
- 250 Grams(1 ¼ cups) Granulated Sugar
- 90 Grams (Scant Cup) Bensdorp Dutch Cocoa Powder
- 3oz (scant ⅓ cup) Vegetable Oil
- 1 Tablespoon Pure Vanilla Extract
- 1 Large Egg Yolk and 1 Large Egg, at room temp.
- ⅛ Teaspoon Baking Powder
- ½ Teaspoon Salt
- 1 Tablespoon Cornstarch/ Cornflour
- 60 Grams (scant ½ cup) All-Purpose/ Plain Flour
- 6oz (¾ Cup) Creamy Peanut Butter (For baking I prefer brands like Jif or Skippy)
Instructions
- Preheat your oven to 350F/180C and line a 9X9 or 8X8 square pan with foil and grease heavily.
- In a large pot add the water, butter, sugar, and cocoa powder. Cook on medium heat for 2-3 minutes until it is all combined together. Take off of the heat and add the oil and vanilla extract.
- Let the mixture sit for 5 minutes then add the egg and egg yolk. Whisk to combine.
- Add the baking powder, salt, cornstarch, and mix to combine. Gently add the flour by using a spatula to fold in until just combined. Do not over mix, this will affect the end product.
- Pour ⅔rds of the batter into the pan and use an angled spatula to spread it out, scoop 4oz (½ Cup) of the peanut butter on top of the batter and use an angled spatula to gently spread it into one even layer, as best as you can. Pour the remaining brownie batter on top and then place the remaining peanut butter in chunks then use a butter knife to gently swirl up and down then across, but do not overmix or you won't have the pretty peanut butter swirls.
- Bake 25-35 minutes. Everyone’s oven is different, for me, the brownies always bake within 29-31 minutes, but I would start checking at 25 minutes for your oven. Don't overbake the brownies. You want a toothpick in the center to come out with moist crumbs, not completely dry. Place the pan on a wire rack to cool completely before cutting.
- Store in an air-tight container on the counter for up to 4 days.
Notes
- Doubling the recipe- I have done it a couple of times in a 9X13 inch pan, I can't remember the exact oven time. I would start checking the brownies at 31 minutes and gauge how much longer- 5 more minutes..etc. I will update when I make them double again.
- Olive Oil- I have made this recipe with olive oil instead of vegetable oil, while not economical I was in a pinch and it worked beautifully!
- Prep Time: 15
- Cook Time: 35
- Category: Dessert
- Method: Bake
- Cuisine: American
Keywords: peanut butter swirled brownies, peanut butter brownie recipe, pb brownies
Ann says
Hi Elizabeth,
I was just wondering why the peanut butter dries out and becomes crumbly, While the brownie part is still fudgy and moist.
Elizabeth Waterson says
Hi Ann, the type of peanut butter can effect it drying out also the peanut butter will dry out quicker than the brownies since peanut butter is much drier to begin with. I personally have not had a problem with dry, crumbly peanut butter. I usually use JIF peanut butter and the brownies are gone in my house by day 2-3. Let me know if I can help with anything else. XX Liz
Maria Zubair says
I have made it. they were good but i burnt mine. I will try again.
Elizabeth Waterson says
Hi Maria, so sad to hear you burnt yours, every oven is different so I do suggest you check ahead of time if your oven runs hot. Goodluck for next time! XX Liz
Maria says
I have made it. they were good but i burnt mine. I will try again. Also i dont know when to add chocolate chunks in the brownies
Elizabeth Waterson says
Hi Maria, sorry for the confusion there shouldn't be any chocolate chunks in this recipe. But if you wanted to add some you could I would add them when you fold the flour in. XX Liz
Maria says
I have one more question: can i use the brownie batter for simple brownies?
Elizabeth Waterson says
Yes you can use it with no peanut butter and just make plain brownies! XX Liz
Maria says
Hey Liz
Used it to cook simple brownies(without peanut butter). The output was so good. Everybody loved it
Thank you so much
★★★★
Elizabeth Waterson says
Hi Maria, thanks for coming back to review the recipe. So glad you enjoyed the brownies!!! Take care. XX Liz