Brownie Mix Peanut Butter Cookies

Name: Brownie Mix Peanut Butter Cookies
Prep time: 10 min
Cook time: 10 min
Total time: 20 min
Yield: 24 cookies
Ingredients: 1 box brownie mix; 1 cup peanut butter; 1 large egg

Highlighted under: Oven Inspiration

I absolutely love how easy and delicious these Brownie Mix Peanut Butter Cookies are to make! With just a few ingredients—including brownie mix and peanut butter—I can whip up a batch of cookies that are soft, chewy, and full of rich chocolate flavor. These cookies come together in no time, making them perfect for a last-minute treat or when I'm craving something sweet. They're sure to impress family and friends, and I often make them for gatherings because everyone raves about them!

Created by

Tamsyn Calder

Last updated on 2026-02-23T19:25:37.912Z

When I first tried making cookies with brownie mix, I was blown away by how wonderfully they turned out. The combination of chocolate and peanut butter creates a decadent treat that’s hard to resist! I remember the first time serving them at a gathering; they disappeared in a flash, and everyone asked for the recipe.

One key tip I’ve learned is to not overbake them. Because of the brownie mix, these cookies remain fudgy and soft. I usually take them out of the oven when the edges are set but the centers still feel a bit underbaked, as they will continue to firm up while cooling!

Why You'll Love These Cookies
Rich chocolate flavor paired with creamy peanut butter
Super soft centers with slightly crisp edges
Quick and easy to make with just three main ingredients
Perfect for cookie cravings or impromptu gatherings

Mastering the Dough

Achieving the perfect dough for Brownie Mix Peanut Butter Cookies is all about consistency. When you combine the brownie mix, peanut butter, and egg, the dough should be thick yet pliable. If the mixture feels too dry, you can add a teaspoon of water or milk to help bind it together. Conversely, if it's too sticky, a small additional sprinkle of brownie mix can help you reach the desired texture for scooping.

It's essential to mix the ingredients thoroughly to ensure even flavor distribution. I usually use a spatula for the initial mixing to combine everything evenly and then use my hands to knead it slightly. This process not only enhances the texture but allows me to gauge the consistency better.

Baking Tips for Success

Timing is crucial for perfectly baked cookies. As they bake for about 10 minutes, keep a close watch starting at the 8-minute mark. The edges should look set while the center will appear soft and slightly underbaked. This stage ensures that the cookies will remain chewy once cooled. If you notice the edges turning too dark, consider lowering your oven temperature slightly in future batches.

Using parchment paper on your baking sheet not only prevents sticking but also aids in even baking. If you notice uneven baking, check the placement of your oven rack. For best results, bake these cookies in the center of the oven, ensuring proper air circulation around them.

Ingredients

Gather these simple ingredients before you start making your cookies:

Ingredients

1 box brownie mix
1 cup peanut butter
1 large egg

Now that you have your ingredients ready, let’s start making these delicious cookies!

Instructions

Follow these steps to bake your Brownie Mix Peanut Butter Cookies:

Preheat the oven

Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

Mix the ingredients

In a mixing bowl, combine the brownie mix, peanut butter, and egg. Stir until well combined into a smooth dough.

Scoop the dough

Using a cookie scoop or tablespoon, drop portions of the dough onto the lined baking sheet, spacing them about 2 inches apart.

Bake

Bake in the preheated oven for about 10 minutes, or until the edges are set and the centers are slightly underbaked.

Cool

Remove from the oven and allow to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.

Once cooled, enjoy your cookies with a glass of milk!

Pro Tips

For an extra touch, you can sprinkle some sea salt on top before baking to enhance the flavors.

Storage and Make-Ahead Tips

These Brownie Mix Peanut Butter Cookies can be made ahead of time and stored in an airtight container at room temperature for up to a week. To keep them fresher longer, I recommend layering the cookies with parchment paper to prevent sticking. If you plan to enjoy them later, consider freezing the uncooked dough. Simply scoop the dough portions onto a baking sheet and freeze until solid before transferring them to a freezer bag for up to three months.

When you're ready to bake frozen dough, there’s no need to thaw it. Just add a couple of extra minutes to the baking time, keeping an eye on the cookies as they bake until the edges are set. This ready-to-bake option is fantastic for satisfying sudden cookie cravings!

Flavor Variations

To add a personal twist to these cookies, consider incorporating chocolate chips, chopped nuts, or even a drizzle of caramel sauce on top before baking. These additions not only enhance the flavor but also create a delightful texture contrast with the soft centers. For a different flavor profile, you might experiment with a flavored brownie mix—like caramel or espresso—for an exciting new taste experience.

If you're catering to specific dietary needs, there are several substitutions you can try. For a gluten-free option, ensure you select a gluten-free brownie mix. Vegan eaters can substitute the egg with a flaxseed meal mixed with water (1 tablespoon of flaxseed meal and 2.5 tablespoons of water) for a binding agent. Adjusting these base ingredients opens up the recipe for everyone to enjoy!

Questions About Recipes

→ Can I use different nut butters?

Yes, you can substitute peanut butter with almond butter or any nut butter of your choice.

→ How should I store leftover cookies?

Store them in an airtight container at room temperature for up to a week.

→ Can I freeze the cookie dough?

Absolutely! You can freeze the dough for up to 3 months. Just thaw and bake as directed when ready to use.

→ How do I know when they are done baking?

Look for set edges with slightly soft centers. They will firm up as they cool.