How to Make Perfectly Soft Peanut Butter Brownies Every Time

I have to share this recipe! These peanut butter brownies have quickly become one of my favorite easy treats. They always come out super soft and fudgy, and that peanut butter swirl on top just makes them next-level delicious. If you’re a peanut butter fan like me, this recipe will totally hit the spot whenever you want something sweet without a lot of fuss.

What I really love about this recipe is how simple it is. Just a box of peanut butter brownie mix and a few extra ingredients, and in about 20 minutes you’ve got something that tastes way fancier than it actually is. And that extra peanut butter drizzle? It makes the brownies super creamy and rich, but you can add as much or as little as you want, it’s totally up to you.

I’ve made these brownies so many times now, they feel like a little comfort whenever I’m craving something sweet and peanut buttery. Whether it’s a quick dessert, a casual get-together, or just one of those days when peanut butter cravings strike, these brownies are always a win.

Ingredients

• 1 Box peanut butter brownie mix (any brand): This is the base that makes these brownies quick and easy.

• 2-4 tbsp peanut butter (pouch was included with my cake box): Adds that creamy peanut butter swirl and extra flavor, use as much as you like!

• 1 egg: Helps bind everything together for a perfect texture.

• 2 tbsp water: Keeps the batter moist and smooth.

• 2 tbsp vegetable oil: Adds richness and keeps the brownies soft.

• 8×8 inch square tin: The ideal size for baking these brownies evenly.

Step-by-Step Instructions

You can find a printable recipe card at the bottom of this post.

1. In a bowl, combine the brownie mix with the water, egg, and vegetable oil.

2. Use an electric mixer or a whisk to blend the ingredients until smooth and well combined.

3. Line an 8×8-inch square tin with parchment paper for easy removal.

4. Pour the brownie mixture into the prepared tin, spreading it evenly.

5. Drizzle peanut butter over the brownie batter. You can add as little or as much as you like, depending on your preference. (For extra creaminess, I like to add an additional 2 tablespoons of peanut butter.)

6. Preheat your oven to 320°F.

7. Place the tin in the oven and bake for 15-18 minutes, or until a toothpick inserted into the center comes out clean.

8. Once baked, remove from the oven and let the brownies cool on a cooling rack.

9. Once cooled, cut the brownies into small squares.

10. Enjoy!

Tips for the Perfect Peanut Butter Brownies

• Don’t be shy with the peanut butter swirl, adding a little extra makes these brownies so much creamier and more delicious.

• Use an electric mixer if you can, but a good whisk works just fine too, just mix until everything’s nice and smooth.

• Keep an eye on the baking time, overbaking dries out brownies, so pull them out as soon as a toothpick comes out with a few moist crumbs.

• Line your pan with parchment paper to make lifting the brownies out super easy and mess-free.

• Let the brownies cool completely before cutting; it helps them set up and keeps them nice and soft inside.

• If you want a little extra peanut butter punch, warm up some peanut butter and drizzle it over the top once they’re cool, trust me, it’s amazing!

Get Creative!

• Try swirling in some chocolate chips along with the peanut butter for an extra gooey surprise.

• Sprinkle chopped peanuts on top before baking for a nice crunch and a little texture.

• Mix in a handful of mini marshmallows for gooey pockets of sweetness throughout the brownies.

• Drizzle melted white chocolate or caramel over the cooled brownies for a fancy finish.

• Add a pinch of sea salt on top before baking to really make that peanut butter flavor pop.

• Swap out the peanut butter for almond or cashew butter if you want to switch things up a bit.

Serving & Storing

• These brownies are amazing on their own, but a scoop of vanilla ice cream on top takes them to dessert heaven.

• Warm them up for a few seconds in the microwave if you want that melty, gooey peanut butter goodness.

• Store leftovers in an airtight container at room temperature for up to 3 days, if they last that long!

• You can also pop them in the fridge for up to a week if you want to keep them fresh a bit longer.

• For longer storage, freeze the brownies in a sealed container or wrapped tightly in foil for up to 3 months. Just thaw overnight before digging in.

• Cut the brownies into small squares for easy grab-and-go snacks or lunchbox treats.