Fudgy Peanut Butter Brownie Cookies

These peanut butter brownie cookies are super fudgy and filled with peanut butter. As they bake, the peanut butter ripples out, creating a beautiful marbled pattern inside! Packed with cocoa powder and melted chocolate, these are the ultimate cookies for peanut butter and chocolate lovers alike!

Chocolate and peanut butter is a delicious, classic flavor combination that's extremely hard to beat. That's why I had to take my viral salted brownie crinkle cookies and stuff them with peanut butter to create these decadent peanut butter brownie cookies!

These are basically peanut butter stuffed brownies shaped like cookies. They have soft, gooey centers with crisp edges and shiny crinkled top like my chocolate snowstorm cookies. Why choose between a brownie and a cookie when you can have both!

I'll admit, these cookies are a little messy to make, but they're so worth it. You only need a mixer, a cookie scoop, and 2 mixing bowls to make them. They're super customizable and can be stuffed with other nut butters and spreads too!

If you love all things fudgy and chocolatey, try small batch brownies, olive oil brownies, or double chocolate chip cookies next! And for more peanut butter cookies, try browned butter peanut butter cookies and peanut M&M cookies.

Ingredient Notes

Here are some notes about the ingredients used. For quantities and full instructions, see the recipe card below.

• Creamy peanut butter- I used JIF creamy peanut butter for these cookies. I don't recommend natural peanut butter because it's too soupy. You need something thick for this recipe! Make sure to measure out the peanut butter and place it in the freezer before using.
• Chocolate- You need 8 ounces of bittersweet or dark chocolate to make the cookie dough. Make sure to use chocolate baking bars (not chocolate chips- they don't melt as easily) with at least 60% cocoa solids for the richest flavor and best structure. More chopped chocolate or chocolate chips are folded into the dough before baking. This can be any type of chocolate, but I chose semi-sweet chocolate chips.
• Oil- Instead of butter, these cookies are made with oil to keep them moist and fudgy. Use a neutral, flavorless oil like canola, avocado, grapeseed, or vegetable oil.
• Eggs & egg yolk- Large eggs bind the ingredients together and encourage spreading. The egg yolk makes them extra rich and chewy. Make sure the eggs are at room temperature so they mix in easily. This also helps the sugar dissolve properly so the cookies get a shiny crust.
• Granulated sugar- This sweetens the dough and helps it stay moist.
• Vanilla extract- A splash of vanilla deepens and enhances the other flavors.
• All purpose flour- This makes up the structure of the cookies. Make sure to measure it in grams using a kitchen scale. If you don't have a scale, fluff up the flour and gently scoop it into your measuring cup.
• Cocoa powder- I prefer Dutch-processed cocoa powder, which is treated with alkali to reduce acidity, creating a deeper, smoother flavor. You can use unsweetened cocoa powder (also called natural cocoa powder) in a pinch, but the flavor and color won't be quite as rich.
• Salt- A little salt offsets the sugar and chocolate for a balanced flavor.

Substitutions

• All purpose flour: I've tested a gluten free version of this recipe with Bob's Red Mill 1-to-1 Baking Flour, and it works great!
• Peanut butter: If you aren't a peanut butter fan, try substituting almond butter, cashew butter, sunflower seed butter, or another kind of nut butter. You could also try chocolate hazelnut spread or Biscoff like these Biscoff butter cookies!

Helpful Equipment and Tools

• 5-quart stand mixer- A mixer fitted with the paddle attachment is needed to whip the eggs. The aeration creates the shiny, crinkled tops! You can also use an electric hand mixer with a large mixing bowl.
• Cookie sheets- I love my cookie sheets from Nordic Ware. They're high quality and last forever! Make sure to use light colored, aluminum cookie sheets. They heat up evenly and won't burn your cookies like dark colored or silicone pans might.
• Parchment paper- These pre-cut parchment paper sheets are a lifesaver. They're so easy to use compared to classic parchment rolls.
• Cookie scoop- You can use a 3-tablespoon cookie scoop to make large brownie cookies. For smaller cookies, use a 1.5 or 2-tablespoon scoop. Keep an eye on the cookies though- they might take less time to bake if they're smaller.

Step by Step Instructions

Let's make peanut butter filled brownie cookies! Before you start, place your pre-measured peanut butter in the freezer. Preheat the oven to 350°F/180°C and line 2 cookie sheets with parchment paper.

STEP 1: First, roughly chop 8 ounces of chocolate and melt it in the microwave, stirring every 15 seconds or so until completely melted and smooth. Stir the oil into the chocolate and let it cool slightly.

STEP 2: Add the eggs, egg yolk, and granulated sugar to the bowl of your stand mixer fitted with the paddle attachment. Beat on high for 2-3 minutes or until the mixture lightens to a pale yellow color.

STEP 3: Next, pour in the oil and melted chocolate mixture and vanilla extract. Mix on medium speed until well combined.

STEP 4: Mix in the flour, cocoa powder, and salt until just combined. Don't overmix as it can make the cookies tough and dense.

STEP 5: Fold in the chopped chocolate or chocolate chips on low speed or with a rubber spatula. This cookie dough is essentially brownie batter, so it will be loose and very sticky.

STEP 6: Next, fill half of your cookie scoop with dough. Press it up the sides and create a small divot or indent for the peanut butter. Scoop about 1 teaspoon of frozen peanut butter into the hole and cover it with more cookie dough.

I don't recommend rolling dough balls in your hands here because the dough is so wet!

STEP 7: Once filled, drop each dough ball on your baking sheets with 1-2 inches between each. Bake for 10-12 minutes at 350°F/180°C until the edges are set. The middles might seem underdone, but they'll keep cooking as they cool. Remember, these are literally brownies in cookie form, so the centers will be gooey!

STEP 8: Remove the cookies from the oven and let them cool on the hot pan for 5-10 minutes before transferring to a wire cooling rack. Let them cool completely, sprinkle with flaky salt, and enjoy!

Expert Baking Tips

• Freeze the peanut butter. The peanut butter filling has to be frozen or it will melt while trying to stuff it in the dough.
• Use room temperature eggs. When mixing the wet ingredients, the sugar dissolves into the eggs. This and the rapid mixing are what create a shiny, crinkled top. Room temperature eggs help the sugar dissolve properly!
• Refrigerate the dough. If you find that the dough is too sticky to scoop or shape, pop it in the fridge for about 20 minutes. It will solidify in the refrigerator, but your tops might not be as shiny when baked.
• Wash your hands. The process of stuffing the dough with peanut butter gets really messy! I recommend washing your hands after every 4 cookies or so since it's hard to get the peanut butter in with messy hands. Wearing disposable food prep gloves is also helpful!

Additions and Variations

Here are some ingredients you can add to your brownie cookies. Note that these ideas have not been tested. If you try one of them, let me know how it goes in the comments!

• Peanut butter chips- Substitute the chocolate chips for peanut chips for extra peanut butter goodness.
• Nuts- Instead of chocolate chips, fold in some chopped almonds (they'd taste like my almond brownies), pecans, hazelnuts, or walnuts for crunch.
• Spices: Try flavoring the dough with a pinch of cinnamon, nutmeg, or even a dash of cayenne for some warmth.
• Cookie butter- Instead of peanut butter, try making these cookies with Biscoff spread!
• Espresso powder- ½ teaspoon of instant espresso powder will deepen the cocoa flavor. I actually add coffee to most of my chocolate recipes, including these chocolate cupcakes and chocolate ganache cake. If you want a more pronounced coffee flavor, add a little more.

Storage and Freezing

Store the cookies in an airtight container at room temperature for 4-5 days. I don't recommend refrigerating them since it'll change the texture!

Freezing

Baked cookies can be frozen in a freezer-safe container or zip-top bag for up to 3 months. Reheat them in the oven for a few minutes for a freshly-baked taste.

To freeze the cookie dough, first freeze them on a baking sheet for 2 hours or until frozen solid. Transfer to a freezer bag and freeze for up to 3 months. You can bake them straight from frozen, no need to thaw. Just an extra minute or 2 onto the bake time.

Frequently Asked Questions

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