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Adding a layer of peanut butter goodness to an ordinary boxed brownie mix (or a plain brownie recipe) makes it extra special!

Why You’ll Love this Peanut Butter Brownie Recipe
Suprise – Cutting into a pan of seemingly regular brownies to reveal a suprise layer of peanut butter is so fun!
Elevates the Ordinary – this recipe transforms a normal brownie into something extra special and bakery-worthy.
Convenient – use this recipe with a boxed brownie mix for a super simple dessert. You can also use this recipe with your favorite plain brownie recipe.
Layered – the layered look of the peanut butter sandwiched in the brownie makes it look impressive, but it’s super simple to make. It’s the perfect dessert for bake sales, parties, holidays, and more!
Ingredients You’ll Need
Peanut Butter – the star ingredient. Adds delicious nutty flavor that goes so well with a fudgy chocolate brownie.
Powdered Sugar – sweetens the peanut buttter and adds structure.
Salt – balances flavors.
Brownie Mix or Recipe – you can use your favorite brownie mix or brownie recipe for this. For the brownies pictured, I used Betty Crocker’s Dark Chocolate Brownie Mix.

Tips for Making Peanut Butter Stuffed Brownies
Use Parchment Paper – when preparing the peanut butter layer, I have found it easiest to use parchment paper to create an even layer. Place a layer of parchment paper down in the pan that you will use for the brownies. Add the peanut butter “dough” on top. Add a sheet of parchment paper on top and press the peanut butter into an even layer.
Prepare the Peanut Butter Layer Ahead of Time – freezing the peanut butter layer ahead of time makes the preparation of the brownies so easy. Add some brownie batter to the pan and spread evenly. Place the frozen sheet of peanut butter on top. Spread with remaining brownie batter. It’s that simple. Having the peanut butter layer frozen allows you to easily place it on top of the brownie batter and easily spread more batter on top without mixing the two together.
Keep Peanut Butter Layer in Freezer Until Ready to Use – while you prepare your brownie batter, keep the peanut butter layer in the freezer. This will ensure it does not defrost ahead of time and you can easily remove the parchment paper and layer it into the brownie batter.
Adjust Amount – this recipe makes enough of the peanut butter layer for a 9 x 13 batch of brownies. If your boxed mix or favorite recipe makes an 8 x 8 batch of brownies, either halve this recipe or double the brownies.

Check Out Other Peanut Butter Recipes:
Equipment
I highly recommend using parchment paper for the preparation of the peanut butter layer.

Peanut Butter Stuffed Brownies (Transforming Boxed Mix or Plain Recipe)
Ingredients
- 1 ½ cup (390 g) creamy peanut butter
- 1 cup (110 g) powdered sugar
- boxed brownie mix or plain brownie recipe, batter prepared according to instructions
Instructions
- In a bowl, mix peanut butter and powdered sugar until well combined.
- Place a piece of parchment in a 9 x 13 baking dish. Dollop the peanut butter mixture on top. Place another layer of parchment paper on top of the peanut butter mixture.
- Press the peanut butter into an even layer.
- Freeze for several hours, or overnight, until peanut butter is solid. Keep frozen until ready to use.
- Prepare the brownie batter according to package or recipe instructions.
- Spread ⅓ to ½ of the brownie batter into a prepared 9 x 13 baking dish.
- Peel one layer of parchment paper off of the frozen peanut butter layer. Place the peanut butter layer, peanut butter-side down, on top of the brownie batter.
- Peel away the remaining parchment paper. Spread remaining brownie batter on top.
- Bake according to package or recipe instructions.
Notes
If you try out this recipe for peanut butter stuffed brownies, I’d love to know what you think! Please leave a comment with a rating below and share a photo of your creation on Instagram using the hashtag #BrooksideKitchen and tag @BrooksideKitchen




