Cake mix peanut butter cookie brownies are the bomb! Rich peanut butter flavor with white chocolate chips that are an ooey gooey dessert everyone in the house will love. They’re so easy because you use yellow cake mix as the base and amp it up with nuts and peanut butter. The best quick treat ever.
It was time to make cake mix peanut butter cookie brownies this afternoon and they came out incredible! Moist, chewy, and just crispy enough on the edges to be perfect. (originally published 4/18, affiliate links present)
Ok so I am a big dessert lover, and peanut butter is on the top of the list of my favorite flavors! In the past we shared how to make brownies out of cake mix but we made strawberry brownies that time.
This is definitely one of our favorite boxed cake mix recipes.
We added some peanut butter chips as well as white chocolate chips to achieve the peanut butter chocolate flavors I love and wahhlahhh, perfection.
Peanut butter cake mix brownies
You want the edges of the brownie part to be lightly browned and the middle will look like they are not done.
BUT just like cookies made with cake mix, when you let them cool in the pan they will continue to cook. Then they’ll be perfect as you see here, so take them out even if you think they aren’t ready.
- A toothpick inserted will come out relatively clean with a little bit of “wetness”. 😉
When we made the strawberry cake mix brownies they took about 20 minutes, but we were at sea level.
Now that we are a bit at altitude in Idaho they took closer to 30 minutes so that is the range.
How to Make Brownies from Cake Mix
I will say when it comes to baking brownies in general there is a large range of what people enjoy. Some love really crispy edges and more of a cake like consistency where we like them just on the verge of being undercooked.
- This is my suggestion to cook these cookie bars perfectly!
Use this easy cake mix peanut butter cookie brownies recipe.
Check them after 20 minutes and see if the brownie batter have stiffened, and the edges are a light brown. If not then add 3-5 minutes and check again.
After the first time you will then know how long it takes for your oven and location.
Then the next time you’ll know what time works perfectly!
Also….if you want peanut butter loaded cake mix brownies then use all peanut butter chips and skip the white chocolate chips.
Or add semi sweet instead of white for a real chocolate peanut butter brownie.
I took this picture so you could see what they look like when you should take them out…just barely golden brown on the edges and do NOT cut them until they are completely cool either.
Put the pan on a cooling rack because they will continue to cook a bit in the pan so they come out super moist like you see at the top.
Once you’ve tried these move on to another cake mix flavor and chips, like red velvet brownies with white chocolate chips!
Just follow this same recipe but substitute the different cake mix flavors and chips for other dessert ideas.
Peanut butter cookie brownies
- Cake mix – this cake mix Betty Crocker works great, 15.25 oz.
- homemade yellow cake mix works too
- Peanut butter – we like creamy best for this
- Peanut butter chips – or use this mix of chocolate & peanut butter chips
- White chocolate chips – we used half and half, you can use all peanut butter if you want overload
- Crushed peanuts – optional, we didn’t add bc I don’t like nuts in my brownies but if you do it would be a good addition
- 8×8 baking dish – I like using glass pans personally
- cooking spray so prepared pan with brownie mix doesn’t stick
- or line with parchment paper
You’ll also want a large bowl to mix dry ingredients.
After you make these you’ve gotta’ try these other yummy peanut butter desserts! They’re all easy recipes your family will enjoy right now.
- Easy Peanut butter brownie in a mug is a winner if you want dessert for one late at night. 😉
- Our peanut butter oatmeal cookie recipe is great
- Peanut butter cookies are a fave
We love these Instant Pot peanut clusters with actual nuts and deep dark chocolate.
- Snowball cookies are fun during the holidays
- Devils food brownies from cake mix
- Peanut butter filled pressure cooker brownie
- Chocolate chip cookie in a mug can have peanut butter chips added to it
If you want another peanut butter layer you can make homemade peanut butter frosting or put ice cream on top once they’re cooled.
Here’s a video showing you how we make these easy peanut butter brownies!
What is the best way to keep brownies fresh?
Let me start by saying that IF we have any leftover brownies there aren’t many. 😉
- Ideally store your brownies in an air tight container with a piece of parchment paper in between so they don’t stick.
- Small freezer bags can be used too. Make sure all air is removed before zipping closed.
- 1-2 days is ideal to maintain moisture.
- Some people add a slice of bread to the top of them to increase the moisture in the container.
Do you store brownies in the fridge?
- I typically do not.
- They stay moister at room temperature.
- You could freeze them for longer storage by cutting them into squares first. Then wrap each one well in plastic wrap and put them all in a freezer bag. Remove air and zip tight. They should last up to 3 months this way.
BUT fresh is always best!!
Peanut Butter Cookie Brownies
- Mix cake mix, peanut butter, eggs and oil in a bowl well until combined and no powder is showing. Preheat oven to 350 degrees now.
- Fold in chocolate chips/peanut butter chips and if you choose to add crushed peanuts fold them in too.
- Spray an 8×8 pan with non stick spray or line with parchment paper.
- Spoon batter into pan and spread out so it is an even thickness across the pan so it cooks evenly.
- Place into the middle rack of your oven for about 25 minutes or until the edges are a light brown. (if you're a bit at altitude you might need 30 min. until edges are golden brown)
- You DO NOT want to overcook these, you want slightly crispy on edges but very soft in the middle. It is important to take out at this point, leave in the pan and allow them to cool on a cooling rack to firm up before slicing.