Reese’s Peanut Butter Brookies

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Half brownie, half peanut butter cookie, and then stuffed with a layer of melty peanut butter, these Reese’s Peanut Butter Brookies are full of chocolate and peanut butter in every bite.

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I’m pretty sure that I’ve created my dream dessert with this recipe. In my opinion, chocolate and peanut butter is the best dessert combination. And, these Reese’s Peanut Butter Brookies do not disappoint. They have a delicious, super chocolatey brownie base. They’re then topped with a layer of peanut butter and covered with peanut butter cookie dough. I really wanted the cookie dough layer to have as much peanut butter as possible, so I added peanut butter into the cookie dough itself, and added in a variety of Reese’s toppings. In this recipe, I used Reese’s peanut butter chips, Reese’s Pieces, Mini Reese’s Peanut Butter Cups, and a Reese’s Bar. So, you can’t tell me that there’s not enough peanut butter in these!

If you’ve never tried brookies before, you are seriously missing out! Two of the best desserts combined in one, what could be better? Plus, regardless of whether you make them in bar or cookie form, they’re a simple, but elevated dessert that’s always guaranteed to be a crowd pleaser.

If you’re a chocolate and peanut butter lover, trust me, you’re going to want to add these to your baking list ASAP. Now, let’s get into the recipe!

Read on for the full recipe for these dreamy Reese’s Peanut Butter Brookies.

Brookies have to be in my top 10 favorite desserts. I swear, they’re life changing. Two classics combined into one dessert? It’s a hard combination to beat. While classic brookies are delicious on their own, I really wanted to take these up a notch and make a recipe specifically for my peanut butter lovers. And the best part: they’re super easy to make! Since we’ll be making brownie batter and cookie dough, this recipe will take a bit longer, but it’s absolutely worth it!

I highly recommend making your cookie dough first. Not only will that give you a little bit of time to let the cookie dough chill in the refrigerator, but it’ll make the assembly process easier and a bit more seamless since everything will be ready to go. For the cookie dough layer, we’ll be using room temperature butter so a stand or handheld mixer is required. The cookie dough comes together quickly in one bowl and is then set aside to prep the brownie batter.

We’ll be using a chocolate mixture, comprised of bittersweet chocolate chips and butter, and dark cocoa powder to achieve the perfect, most delicious brownie layer. And, of course, adding in a healthy amount of semisweet chocolate chips because they’re not brownies without chocolate chips! Once the brownie batter is ready to go, you can start baking the first layer of the brookies. The brownies will bake for 15 minutes which is just enough time for them get a nice, solid, crinkly bake on top. If your brownies don’t look set on top, continue baking them for 1 to 2 minutes, as needed. Your brownies must be set on top (they cannot be liquidy at all) in order to add the peanut butter layer.

Once the brownie layer is set on top, remove the pan from the oven, and cover it in a generous layer of peanut butter. If your peanut butter is thick, you can microwave it in a microwave-safe bowl in 5 to 10 second increments to make it easier to spread. Please be careful while spreading the peanut butter as the top layer of the brownies is pretty fragile. If you’re not careful, it’s easy to accidentally tear into the brownies. Once the peanut butter has been spread evenly across the brownies, it’s time for the cookie dough layer! Break apart the cookie dough into smaller pieces and flatten it with the palm of your hand. Place the cookie dough pieces over the peanut butter. The cookie dough pieces can overlap. If you don’t have enough cookie dough to cover every gap, don’t worry. The cookie dough will spread as it bakes and cover those tiny gaps.

Before placing the brookies into the oven, top the cookie dough layer with chopped Mini Reese’s Peanut Butter Cups and chopped Reese’s Bar pieces. You can never have too much chocolate and peanut butter, right? The brookies will then bake for an additional 25 to 30 minutes or until the cookie dough layer is a light golden color and the bars are set. A very slight jiggle is okay, but it should not jiggle a lot.

Once the brookies have been removed from the oven, top them with flaky sea salt and then let them set for at least 3 hours or overnight. I know, I want to eat my desserts as soon as they come out of the oven too, but it really is best to let these brookies set and cool before slicing. If you slice them while they’re hot, they will be very delicious, but also very messy.

I’ve included below some additional Tips for Success as well as some answers to frequently asked questions, so be sure to scroll down to see those. If you need help with this recipe, DM me on Instagram and I can help answer any questions you have.

Other recipes you may like:

• Rich & Fudgy Nutella Stuffed Brookies
• Chocolate Dipped Peanut Butter Stuffed Reese’s Cookies
• Reese’s Pumpkin Stuffed Cookies
• Gooey Oreo Cookie Butter Lava Cookies
• Chocolate Dipped M&M Oreo Cookies

Ingredients you’ll need:

• Unsalted butter
• Bittersweet chocolate chips
• Granulated sugar
• Brown sugar
• Vanilla extract
• Eggs
• Creamy peanut butter (I used Jif)
• All-purpose flour
• Dark cocoa powder
• Baking soda
• Salt
• Semisweet Chocolate Chips
• Peanut butter chips
• Reese’s Pieces
• Mini Reese’s Peanut Butter Cups
• Reese’s Bar – I found mine at CVS!
• Flaky sea salt

Kitchen tools you’ll need:

• 9-inch square baking pan
• Parchment paper
• Mixing bowls
• Dry ingredient measuring cups
• Adjustable measuring cup – highly recommend for measuring the peanut butter!
• Spatula
• Whisk
• Stand or handheld mixer

How to make these unreal Reese’s Peanut Butter Brookies

I like to start by making the cookie dough layer first so that it can chill in the refrigerator for a bit!

Cookie Dough Layer

Combine 6 tbsp unsalted butter, ¾ cup brown sugar, and 2 tbsp granulated sugar in a stand mixer (or using a handheld mixer) on medium speed. Beat for about 2-3 minutes or until the mixture is light and fluffy.

Add 1 egg, 1 tsp vanilla extract, and ⅓ cup creamy peanut butter and beat until combined.

In a bowl, whisk together 1½ cups  + 1 tbsp all-purpose flour, ½ tsp baking soda, and ½ tsp salt. Gradually add the dry ingredients on low speed until just combined.

With a rubber spatula, gently fold in ½ cup peanut butter chips and ⅓ cup Reese’s pieces.

Cover the bowl with plastic wrap and set the cookie dough in the refrigerator to chill.

Brownie Layer

Preheat the oven to 350 degrees Fahrenheit. Line a 9-inch square baking pan with parchment paper. Spray the parchment paper with nonstick cooking spray.

Over medium heat, melt 8 tbsp unsalted butter and 4 oz (½ cup) bittersweet chocolate chips in a medium-sized saucepan. Stir the mixture until it’s smooth, then remove from heat.

While the chocolate mixture is cooling, pull together the dry ingredients. In a medium- sized bowl, whisk together 1¼ cup all-purpose flour, ¼ cup dark cocoa powder, and ½ tsp salt. Set aside.

In a large bowl, combine ½ cup brown sugar, ½ cup granulated sugar, 2 eggs, and 1 tsp vanilla extract. Whisk until fully combined and smooth. Add in the chocolate mixture and whisk again until smooth.

Fold the dry ingredients in with the wet ingredients. Use a rubber spatula or wooden spoon and mix until everything is just combined.

Fold in ¾ cup semisweet chocolate chips.

Pour the brownie batter into the bottom of the prepared pan, creating an even layer. Place the pan into the oven and bake for 15 minutes.

Assembly

After 15 minutes, remove the brownies from the oven and gently spread ½ cup creamy peanut butter on top of the brownie layer. Be careful not to break the top layer of the brownies.

Break the cookie dough into smaller pieces and flatten them out with the palm of your hand. Place the cookie dough pieces on top of the peanut butter, creating an even layer. If the cookie dough doesn’t cover all of the peanut butter, that’s okay – the cookie dough will spread while it’s baking.

Top the cookie dough layer with chopped Mini Reese’s Peanut Butter Cups and chopped Reese’s Bar pieces.

Baking & Serving

Place the pan into the oven and bake for an additional 25 to 30 minutes. The brookies are done when the cookie layer is set and light golden in color.

As soon as the brookies are done baking, top them with flaky sea salt.

Let the brookies cool and set completely before slicing. I’d recommend waiting at least 3 hours or overnight before slicing.

Use a knife to slice the bars into 12 (larger) or 16 (smaller) pieces.

Store in an airtight container at room temperature for up to 5 days or freeze for up to 3 months.

Tips for success

• This recipe calls for room temperature ingredients so be sure to take your butter and eggs out about 1 to 2 hours prior to baking. In a pinch, you can carefully soften butter in the microwave. Place it in a microwave-safe container and microwave in 5 to 8 second increments until the butter is just softened (not melted!). Additionally, if you forget to take your eggs out in advance, you can run them under lukewarm (not boiling hot) water and warm them up.
• Measuring your dry ingredients correctly is key! Before you measure out your flour, take a spoon, run through it, and fluff it up. This helps loosen up the flour and gets rid of any clumps. Then, use your spoon to pick up the flour and place it into your measuring cup. Do not scoop up the flour directly with your measuring cup — you will mostly likely end up with too much flour. For measuring dry ingredients, you should be using measuring cups for dry ingredients (these are the ones that I use). However, if you choose to bake using grams and prefer to weigh out your ingredients with a kitchen scale, you can use an online conversion calculator (like this one from Inch Calculator) to convert the recipe.
• Let the brookies cool completely before slicing them! This is crucial. If you slice them while they’re still warm, they will be very messy as the middle layer is gooey peanut butter. I highly recommend letting them cool completely (this may take 3 hours) or wait overnight before slicing. You can also place them in the refrigerator which will help them chill and set.
• Do not overmix your brownie batter or cookie dough. We want these brookie bars to be very soft and chewy. Overmixing (especially with the peanut butter in the cookie dough) can lead to a dry, crumbly texture which we do not want!
• Always use the bake time listed as simply a guide. Instead, go by how the bars look to determine if they should be removed from the oven. Oven temperatures can vary (your friendly reminder to get yourself an oven thermometer), so the time it takes to bake the brookies may vary for you. When the cookie bar layer is lightly golden on top and set, they’re ready to be removed from the oven.

FAQs

Can this recipe be doubled?

Yes, simply use a 9×13 inch pan and double the ingredients.

Can I use any brand of peanut butter?

For the peanut butter layer (between the brownie and cookie dough layers), you should be okay to use any brand of peanut butter. For the peanut butter that the cookie dough calls for, I used Jif/Skippy which has a thicker consistency. Natural peanut butters are a bit more runny and could impact the cookie dough. I can’t say for certain how it will turn out with another brand, but should you choose to use something other than Jif/Skippy, keep an eye on how your dough comes together. If it’s too soft or runny, add an extra tablespoon of flour until you reach the desired consistency. The dough should be easy to scoop and flatten with your hands. It should not be tacky or stick to your hands.

Do I have to chill the cookie dough?

No, but I highly recommend it as it makes it easier to work with the cookie dough so you can carefully spread it over the other layers.

How to store

Store the brookies in an airtight container at room temperature for up to 5 days or freeze for up to 3 months in a freezer-safe container or bag. If freezing, set the brookies out for at least 20 to 30 minutes and let them come to room temperature prior to consuming. Or, heat them up in the microwave for about 30 to 45 seconds and they’ll be delicious, hot, and gooey.

Dreamy, delicious, and full of chocolate and peanut butter, these Reese’s Peanut Butter Brookies are an absolute must bake. The perfect pairing of flavors and loaded with so many different Reese’s toppings, these brookie bars have to be one of my all-time favorite desserts. I hope you all love them as much as I do!

If you try this recipe, share and tag me on socials using @itsbrunchoklock or #itsbrunchoklock.