Peanut Butter Swirl Brownies
These Peanut Butter Swirl Brownies are an easy way to dress up a boxed brownie mix. A mixture of peanut butter and powdered sugar is swirled into the chocolate batter before baking creating, a delicious combination of chocolate and peanut butter in every bite.
Peanut butter and chocolate is one of my favorite flavor combinations. Lunch lady chocolate peanut butter bars are a treat I make often and they are a popular recipe on the blog.
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Why You’ll Love This Recipe
- Simple Ingredients – You only need a handful of ingredients to make this easy dessert. You may already have them in your pantry.
- No Complicated Techniques – The peanut butter mixture is easy to prepare and swirl into the batter.
- Easy to Make Ahead – Bake in advance for parties, potlucks, Christmas cookie trays, or whenever you need a dessert ready to go.
- A Crowd Favorite – Chocolate and peanut butter make this an easy choice when you’re feeing a crowd.
Ingredients for Peanut Butter Swirl Brownies
- Fudge Brownie Mix
- Oil, Water, and Eggs called for in preparation
- Creamy Peanut Butter
- Powdered Sugar
Find the full instructions in the recipe card below.
Tips and Suggestions
- Sift the powdered sugar before combining it with the peanut butter. It’s nearly impossible to get the lumps out once you mix the two. I initially tried mixing with a whisk but found a spatula to work better.
- If you need to microwave the peanut butter longer, do so in small increments to avoid overheating.
- The toothpick test won’t work well because the peanut butter mixture can give you a false sense that the brownies are done.
- Swirling is fun, but don’t overdo it. YOu can swril the peanut btter into the brownie batter too much. It will end up being mixed it rather than ribbons throughout the batter.
More Brownie Recipes
If you like brownies like we like brownies, in addition to this peanut butter brownie recipe, try candy bar brownies, molten lava brownies, Oreo brownies, and frosted Mexican brownies. I sent the Oreo brownies to my son at college and I got a phone call after the first bite that they are the best I’ve ever made!
How do you store peanut butter swirl brownies?
Cover the pan with aluminum foil or transfer them to an airtight container, and kee them on the counter at room temperature. For best flavor, keep for up to 4 days. While they don’t need refrigeration, you can put them in the fridge.
Can I use any boxed brownie mix?
Not all brownie mixes are the same size. Use one that will easily make a 9×13 size pan. Fudge is a preferred variety, though.
How do I get a good peanut butter swirl in brownies?
Drop spoonfuls of the peanut butter mixture over the brownie mixture. Gently swirl with a butter knife through the brownie batter but being careful not to mix it too much. You want to see the swirls but still have peanut butter in every bite.
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Peanut Butter Swirl Brownies
Ingredients
- 1 box fudge brownie mix, 18.3 ounce size, I used Duncan Hines
- eggs, oil, and water called for on the brownie box
- 1 cup creamy peanut butter
- ¼ cup powdered sugar, sifted
- non-stick baking spray
Instructions
- Preheat the oven to 350℉. Spray the bottom of a 9×13-inch baking pan with nonstick baking spray.non-stick baking spray
- Prepare the brownie mix according to the package directions using the water, oil, and eggs on the package. Spread the brownie mixture evenly in the prepared pan.1 box fudge brownie mix, 18.3 ounce size, I used Duncan Hines, eggs, oil, and water called for on the brownie box
- In a microwave safe bowl, microwave the peanut butter on high for 30 seconds. Add the powdered sugar and stir until smooth.1 cup creamy peanut butter, ¼ cup powdered sugar, sifted
- Drop the peanut butter mixture, by teaspoonfuls, onto the brownie mixture. Gently swirl the two mixtures together with a knife, making sure you have swirls throughout the pan.
- Bake 29 to 33 minutes or until the center is set. Cool completely on a wire rack before cutting.
