Peanut Butter Brownie Swirl Cookies Recipe

These cookies combine everything that’s addictive about brownies and peanut butter cookies into one treat. The brownie portion stays soft and fudgy while the peanut butter dough adds a salty-sweet richness. I’ve found they’re basically impossible to mess up – even slightly overbaked, they maintain their chewy texture thanks to the peanut butter.

They’re great for bake sales or potlucks since they travel well and don’t need frosting. The marbled look also makes them stand out on a cookie plate. While they take a bit more effort than basic cookies, the dramatic swirled effect is worth the extra steps. Make them when you want to impress but don’t want to risk a complicated recipe going wrong.

What you need for Peanut Butter Brownie Swirl Cookies

How to make Peanut Butter Brownie Swirl Cookies

Let me walk you through making these eye-catching cookies that combine two favorite flavors. I’ve made these countless times, and getting the swirl just right is easier than you might think.

1. Start by letting butter soften at room temperature for about an hour – you should be able to easily press your finger into it, but it shouldn’t be melty. Preheat your oven to 350°F and line two baking sheets with parchment paper.

2. In a large bowl, beat the softened butter and peanut butter together until they’re completely smooth and well-combined, about 2 minutes. You’ll want to scrape down the sides of the bowl at least once. Add both sugars and cream until the mixture looks light and fluffy – this usually takes about 3 minutes and the color will become noticeably lighter.

3. Beat in 2 eggs, one at a time, mixing until each one disappears completely into the batter. If you see any streaks of egg, keep mixing.

4. In a separate bowl, whisk together your flour, baking powder, salt, and baking soda. Add this dry mixture to your peanut butter mixture in three portions, mixing on low speed just until you don’t see any dry flour. The dough will be pretty thick at this point.

5. Now for the brownie batter: In another bowl, combine the brownie mix, vegetable oil, 2 eggs, and water. Mix until well combined – it should be thick but still fluid enough to drop from a spoon.

6. Here’s where it gets fun: Take about 2 tablespoons of peanut butter dough and roll it into a ball. Make a thumbprint-sized indent in the center. Drop about 1 teaspoon of brownie batter into the indent, then take another small piece of peanut butter dough and partially cover the brownie batter. Don’t worry about making it perfect – the messier the better for a nice swirl effect.

7. Place the cookies about 2 inches apart on your prepared baking sheets. These will spread a bit while baking.

8. Bake for 12-14 minutes, rotating the pan halfway through. You’re looking for edges that are just starting to turn golden brown, while the centers should still look slightly soft. If you tap the edge of a cookie lightly, it should feel set but not hard.

9. Let them cool on the baking sheets for 5 minutes – they’ll be too soft to move right away. Then transfer them to a wire rack to cool completely. The brownie swirl will firm up as they cool but stay slightly fudgy.

Makes about 24-28 cookies, depending on size. The raw dough can be a bit sticky to work with, so if it gets too soft while you’re shaping the cookies, pop it in the fridge for 15 minutes to firm up.

Peanut Butter Brownie Swirl Cookies

Peanut Butter Brownie Swirl Cookies

Chewy peanut butter and fudgy brownie dough swirled together into one decadent cookie, combining the best of both worlds. A rich and irresistible treat!

Print Recipe Pin Recipe

Prep Time 30 minutes mins

Cook Time 12 minutes mins

Cooling time 30 minutes mins

Total Time 1 hour hr 12 minutes mins

Servings 24 cookies

Ingredients

  

• 1 cup unsalted butter softened
• 1 cup creamy peanut butter
• 1 cup granulated sugar
• 1 cup packed brown sugar
• 2 large eggs
• 2½ cups all-purpose flour
• 1½ teaspoons baking powder
• ½ teaspoon salt
• 1 teaspoon baking soda
• 1 box brownie mix 18.3 oz
• ⅓ cup vegetable oil
• 2 large eggs for brownie mix
• 2 tablespoons water

Instructions

 

• Start by letting the butter soften at room temperature for about an hour – you should be able to easily press your finger into it, but it shouldn’t be melty. Preheat your oven to 350°F and line two baking sheets with parchment paper.
• In a large bowl, beat the softened butter and peanut butter together until they’re completely smooth and well-combined, about 2 minutes. You’ll want to scrape down the sides of the bowl at least once. Add both sugars and cream until the mixture looks light and fluffy – this usually takes about 3 minutes and the color will become noticeably lighter.
• Beat in 2 eggs, one at a time, mixing until each one disappears completely into the batter. If you see any streaks of egg, keep mixing.
• In a separate bowl, whisk together your flour, baking powder, salt, and baking soda. Add this dry mixture to your peanut butter mixture in three portions, mixing on low speed just until you don’t see any dry flour. The dough will be pretty thick at this point.
• Now for the brownie batter: In another bowl, combine the brownie mix, vegetable oil, 2 eggs, and water. Mix until well combined – it should be thick but still fluid enough to drop from a spoon.
• Here’s where it gets fun: Take about 2 tablespoons of peanut butter dough and roll it into a ball. Make a thumbprint-sized indent in the center. Drop about 1 teaspoon of brownie batter into the indent, then take another small piece of peanut butter dough and partially cover the brownie batter. Don’t worry about making it perfect – the messier the better for a nice swirl effect.
• Place the cookies about 2 inches apart on your prepared baking sheets. These will spread a bit while baking.
• Bake for 12-14 minutes, rotating the pan halfway through. You’re looking for edges that are just starting to turn golden brown, while the centers should still look slightly soft. If you tap the edge of a cookie lightly, it should feel set but not hard.
• Let them cool on the baking sheets for 5 minutes – they’ll be too soft to move right away. Then transfer them to a wire rack to cool completely. The brownie swirl will firm up as they cool but stay slightly fudgy.