These peanut butter stuffed brownies hide a thick layer of creamy peanut butter between two layers of rich, fudgy chocolate batter. Every square has a salty and sweet center that stays soft after baking.
You only need one pot, one bowl, and an 8×8 inch pan, and the batter takes about 15 minutes to mix. The brownies bake in under 30 minutes and slice cleanly once they have cooled, so they work well for gifts, potlucks, and weeknight treats.
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Why This Peanut Butter Stuffed Brownies Recipe Works
A buttery chocolate base made with dark chocolate chips and cocoa gives the brownies a deep flavor that stands up to the rich peanut butter. Using both melted chocolate and cocoa powder keeps the crumb fudgy rather than cakey.
Pouring half the batter into the pan, spreading peanut butter over it, and covering it with the rest creates a distinct center layer. The filling bakes into a soft, fudge like ribbon instead of leaking out the sides.
The flaky salt on top balances the sweetness, and the small amount of flour keeps the texture dense. The recipe uses basic pantry ingredients, so there is nothing special to hunt down.
Ingredients for Peanut Butter Stuffed Brownies
- 14 tablespoons (1 3/4 sticks) unsalted butter
- 1 1/4 cups dark chocolate chips (7 ounces)
- 1 cup loosely packed brown sugar
- 3 large eggs, lightly beaten
- 1 teaspoon vanilla extract
- 1/2 cup all purpose flour
- 1/4 cup unsweetened cocoa powder
- 1/8 teaspoon kosher salt
- 1 cup smooth peanut butter, for the filling
- 1/4 teaspoon flaky salt, for the top
Peanut butter. Use a smooth, creamy peanut butter so the filling spreads without tearing the bottom layer. Natural styles that separate tend to turn greasy, so stir well first.
Dark chocolate chips. They melt into the butter for a glossy, fudgy base. Semi sweet chips also work if you like a sweeter brownie.
Brown sugar. It adds moisture and a light caramel taste. Keep it loosely packed so the batter does not turn too sweet next to the peanut butter.
Eggs. Lightly beaten eggs mix in smoothly and give the brownies structure. Let the chocolate mixture cool a little first so the eggs do not scramble.
Flour and cocoa. Whisk them with the salt before adding so the dry mix is even. A small amount of flour is what keeps the squares dense and fudgy.
How to Make Peanut Butter Stuffed Brownies
1. Prepare the pan. Heat the oven to 350 degrees F. Grease an 8×8 inch pan and line it with parchment paper for easy lifting.
2. Melt the chocolate. Melt the butter and chocolate chips in a pot over low heat, stirring until smooth, then remove from the heat.
3. Add sugar, eggs, and vanilla. Stir in the brown sugar until combined, then mix in the eggs and vanilla until the batter looks glossy.
4. Mix the dry ingredients. Whisk the flour, cocoa powder, and salt in a bowl. Stir them into the chocolate mixture until just combined.
5. Layer the batter. Pour half of the batter into the pan and smooth it out. Spoon the peanut butter on top and spread it gently, leaving a thin border at the edges.
6. Cover and sprinkle. Pour the remaining batter over the peanut butter and spread carefully to the corners. Sprinkle the flaky salt over the top.
7. Bake and cool. Bake for 25 to 30 minutes, until a toothpick comes out mostly clean with a few moist crumbs. Cool completely in the pan before cutting into 9 squares.
How to Serve Peanut Butter Stuffed Brownies
Serve the squares at room temperature with a cold glass of milk or a scoop of vanilla ice cream. For a dessert tray, pair them with fudgy chocolate chunk brownies and a slice of gooey brownie pie. They also look great beside a stack of soft double chocolate chip cookies or a few wedges of New York cheesecake.
How to Store and Reheat Peanut Butter Stuffed Brownies
Store the cooled brownies in an airtight container at room temperature for up to 4 days. For longer storage, keep them in the refrigerator for up to a week or wrap and freeze for up to 3 months. Let refrigerated squares sit out for a few minutes before serving so the peanut butter layer softens.
Tips and Variations for Peanut Butter Stuffed Brownies
Cool the chocolate. Let the melted chocolate mixture cool for a few minutes before adding the eggs.
Warm the peanut butter. If your peanut butter is stiff, warm it in the microwave for a few seconds so it spreads easily.
Keep a border. Leave a thin border around the filling so it stays sealed inside the batter.
Do not overmix. Stop stirring once the dry ingredients disappear for a soft, fudgy crumb.
Try crunchy. Crunchy peanut butter adds texture, though smooth is easier to spread.
Cut clean squares. Chill the cooled pan for one hour, then use a sharp knife wiped clean between cuts.
Add chopped peanuts. Sprinkle a handful over the top with the flaky salt for extra crunch.
Skip the batter taste. The batter contains raw eggs, so avoid sampling it before baking, and see this Purdue Extension guide to storing leftovers for general storage times.
Frequently Asked Questions About Peanut Butter Stuffed Brownies
How long do peanut butter stuffed brownies need to bake?
They bake for 25 to 30 minutes at 350 degrees F. Start checking at 25 minutes and pull the pan when a toothpick comes out mostly clean with a few moist crumbs.
Can I freeze peanut butter stuffed brownies?
Yes. Wrap cooled squares individually and freeze in a sealed container for up to 3 months. Thaw at room temperature before serving.
How do I keep the filling inside peanut butter stuffed brownies?
Spread the peanut butter in a thin even layer and leave a small border at the edges. Then cover it fully with the second layer of batter so the filling stays sealed during baking.
Can I use crunchy peanut butter?
Yes, crunchy peanut butter works and adds texture. Warm it slightly if it is hard to spread.
What size pan should I use?
An 8×8 inch pan gives thick squares. A larger pan makes thinner brownies that bake faster, so check them earlier.
Peanut Butter Stuffed Brownies
Equipment
- 8×8 inch baking pan
- Parchment paper
- Medium pot
- Whisk or spatula
Ingredients
Main Ingredients
- 14 tbsp unsalted butter 1 3/4 sticks, cut into pieces
- 1 ¼ cup dark chocolate chips 7 oz
- 1 cup brown sugar loosely packed
- 3 large eggs lightly beaten
- 1 tsp vanilla extract
- ½ cup all purpose flour spooned and leveled
- ¼ cup unsweetened cocoa powder
- ⅛ tsp kosher salt
- 1 cup smooth peanut butter for the filling
- ¼ tsp flaky salt for sprinkling on top
Instructions
Cooking
- Prepare the pan. Heat the oven to 350 degrees F. Grease an 8×8 inch pan and line it with parchment, leaving an overhang. Melt the base. Melt the butter and chocolate chips in a pot over low heat for 3 to 4 minutes, stirring until glossy. Remove from the heat and cool 5 minutes.
- Mix the batter. Stir in the brown sugar, then the eggs and vanilla until the batter looks shiny and thick.
- Add the dry mix. Whisk the flour, cocoa, and kosher salt, then fold into the pot until no dry streaks remain.
- Layer the filling. Pour half of the batter into the pan, spoon the peanut butter on top, and spread it to within 1/2 inch of the edges. Cover with the rest of the batter.
- Bake. Sprinkle with the flaky salt and bake 25 to 30 minutes, until a toothpick shows a few moist crumbs.
- Cool and slice. Cool completely in the pan, about 30 minutes, then lift out and cut into 9 squares.
