Peanut Butter Swirl Chocolate Chip Cookie Bars

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Peanut Butter Swirl Chocolate Chip Cookie Bars are loaded with Reese’s pieces and milk chocolate chips. These festive cookie bars are the perfect combination of peanut buttery chocolate goodness- perfect for all your fall and Halloween baking!

As I write this, it’s a cold, rainy, autumn morning here in Norther Nevada, which means it’s the perfect cookie baking weather! And these peanut butter swirl chocolate chip cookie bars are seriously delicious. Dangerously good in fact. I wont judge if you eat the whole pan to yourself… I mean, it tis’ the season, right?! And with Halloween in a few weeks, I just had to make something fun and ‘spooky’ for all of us who are still kids at heart. Plus, kids love to help assemble these cute little bars- so it’s the perfect family fun Halloween themed baking day activity!

There is just something about chocolate and peanut butter together that reminds me of Halloween, probably because my favorite candy as a kid after trick-or-treating was always Reese’s. Picking out all the candy that was peanut butter and chocolate first before moving on to my second favorites, which were kit-kats and 100 grands, was a seasonal ritual. But you just can’t compete with Reese’s! Peanut butter and chocolate are one of the best combinations ever, and these cookie bars are the perfect way to enjoy it. So whatever your fall and Halloween plans include, make sure these cookie bars are apart of it. I promise, you will not regret it!

To really take these cookie bars to the next level, I made a browned butter base for the dough. Browning butter is always a good idea, and these cookies are no exception. Browned butter adds such a lovely, complex nutty flavor that really puts your baked goods over the top! Plus, it compliments the rich peanut butter and chocolate together so well.

Being totally honest, these bars are rich. They’re sweet, salty and the perfect indulgent treat.

So let’s get to some of the details!

Peanut Butter Swirl Chocolate Chip Cookie Bar Ingredients:

Ingredients you will need to make these cookie bars:

• Parchment paper
• an 8×11 casserole pan
• brown butter, cooled
• dark brown sugar
• eggs
• vanilla
• all purpose flour
• baking soda
• milk chocolate chips
• reese’s pieces chips
• creamy peanut butter
• salt
• monster eye candies for decorating (optional)

Making Peanut Butter Swirl Chocolate Chip Cookie Bars:

You will start by browning the butter (tips on browning the butter below). After the butter has browned pour the butter into a heat proof bowl and place in the freezer for 15 minutes to cool.

Next, In the bowl of a stand mixer, beat the butter, brown sugar and white sugars together. Add the vanilla and eggs and beat until smooth. Slowly add the dry ingredients and mix until the flour is fully incorporated.

Using a wooden spoon, gently mix in the chocolate chips and Reese’s chips. Spread half of the dough at the bottom of the prepared pan, dollop the peanut butter on top, then add the remaining cookie dough over the peanut butter. Gently spread. It will look messy- that’s okay! Then bake.

When the cookies are done baking, add the monster eyes on top if using, and allow to cool completely before serving.

Peanut Butter Swirl Chocolate Chip Cookie Bar Tricks and Tips (and treats):

Browned Butter: If you have never browned butter before, don’t be intimidated- its so easy! Browned butter is one of my best kept secrets, which I guess isn’t really a secret anymore. I do tent to post a lot of browned butter goodness like these Dark Chocolate Sea Salt Brown Butter Shortbread Cookies , and this amazing Browned Butter Balsamic Ravioli with Walnuts and Fried Sage, but the flavor honestly can’t be beat!

In a medium saucepan, you will melt the butter over medium high heat. As the butter melts and bubbles, it will eventually start to foam and have a nutty aroma. As the foam begins to subside and the butter has a deep amber color, its time to take off the heat. Put the browned butter in a heat proof bowl, and set in the freezer for 15 minutes to cool.

Pan Size: I wanted these peanut butter swirl cookie bars to be extra thick so I used a smaller 8×11 baking pan. If you want your cookie bars to be on the thinner side, use a 9×13 greased baking ban. It’s important to note, depending on the size pan you use determines how long these cookies will need to bake up. If you want them thicker, they will bake for 35-40 minutes. Thinner cookies will only need 22-25 minutes.

Spreading the Dough: When assembling the cookie dough at the bottom of the pan, you’re going to want to use your fingers to press into the bottom and sides of the pan to form. Then once the bottom layer is ready, you’re going to dollop peanut butter over the top, add the remaining dough over the peanut butter, and gently spread. The bars may appear messy and it’s okay if the dough doesn’t fully cover the peanut butter. As the cookie bars bake, the peanut butter will spread on it’s own leaving pockets of delicious peanut butter goodness!

Peanut Butter: As much of a fan I am of natural peanut butter, for this recipe you’re going to want to skip all natural and use creamy peanut butter such as Skippy’s.

Parchment Paper: I love using parchment paper for baking. It’s so convenient, especially if you’re concerned about your baked goods sticking! I would recommend using parchment paper for easy removal after the bars have cooled, but if you don’t have parchment paper on hand, butter or spray the baking dish with cooking spray to ensure the cookie bars wont stick.

Cooling: As hard as it will be, you must allow these cookie bars to cool completely in the pan before attempting to cut them- or else it will be one big ooey gooey mess! I left them to cool for 30 minutes in the pan before cutting.

And once these Peanut Butter Swirl Chocolate Chip Monster Cookie Bars have cooled, it’s time to indulge!

These are so perfect for a fun, family filled baking day. I hope you love these Halloween inspired cookie bars as much as we do! And if you give them a try, be sure to leave us a comment and rating below! I truly love hearing from you! It’s my passion to inspire others, so I truly hope you feel inspired to bake up something delicious this season!

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I hope you have a wonderful fun filled October!

More fall inspired treats to make this month:

• Pumpkin Pecan Streusel Muffins with Whipped Maple Butter
• Overnight Orange Brioche Cinnamon Rolls
• The Best Cinnamon Apple Pie Bars with Streusel

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