M&M Peanut Butter Cookie Bars

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Soft and chewy cookie bars bursting with peanut butter goodness, M&M’s and chocolate chips. This recipe is easy, delicious, and the perfect treat for any occasion!

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These M&M Peanut Butter Cookie Bars have stolen my heart.

I might say a lot of romantic things about cookies, but these bars are truly something special.

I’m not joking, I couldn’t stop eating these! I even put them in the freezer to save for an upcoming camp trip.

They gone.

I won’t apologize for it. These bars are so chewy and soft, very peanut buttery and they look super festive with all those cute little M&M’s stippled throughout.

What can I say? I’m weak!

The best thing about these bars is that the dough is super easy to make and doesn’t need to be chilled prior to baking.

This means you can whip up a batch in a flash! And it’s a good thing too– because these cookie bars are literally perfect for any occasion that calls for a delicious dessert.

On top of that, these bars yield quite a few, so they’re perfect for a crowd!

Let’s go make a pan right now!

How To Make M&M Peanut Butter Cookie Bars

Makes 24 Bars

Ingredients you’ll need:

• 1 1/2 sticks (3/4 cup) of unsalted butter, softened but still cool
• 1 cup of smooth peanut butter
• 3/4 cup of dark or light brown sugar
• 1/2 cup granulated sugar
• 1 whole large egg + 1 large egg yolk
• 1 teaspoon vanilla extract
• 2 1/4 cups all purpose flour
• 1 teaspoon baking powder
• 1/2 teaspoon baking soda
• 1/2 teaspoon salt
• 1 cup of M&M’s
• 1 cup semisweet chocolate chips

Instructions:

Preheat the oven to 350°.

Line a 13 X 9 pan with two pieces of aluminum foil, crisscrossed in the center, and with a little overhang on the sides. Spray the foil lined pan with cooking spray (or grease with butter) and set aside.

With a mixer (stand or hand) beat the butter until smooth.

Add peanut butter and beat until fluffy.

Next, add the sugars and beat the mixture until it’s well incorporated and slightly lighter in color. Scrape down the sides of the bowl with a rubber spatula.

Add the whole egg, egg yolk, and vanilla and mix until just blended.  

With the mixer on low, add the flour, baking soda, baking powder, and salt. Mix until the flour is almost fully incorporated in the dough–there should still be visible streaks of flour showing.

Add the M&M’s and chocolate chips and gently fold by hand until fully incorporated. Do not overmix.

Press cookie dough into the prepared 13 x 9 baking dish.

Bake at 350° for 22 min, until the edges are lightly browned and puffed and the center is just set.

Let the bars cool completely at room temperature.

Once cooled, gently lift bars from the pan using the foil overhangs and set onto a cutting board.

Carefully remove the foil from the bars, and trim the edges if desired.

Cut into 24 neat squares and enjoy!

Tips for making the best M&M Peanut Butter Cookie Bars

Here are a couple of tips to make sure your bars come out beautiful and super soft and chewy every time:

1. Don’t over mix the dough! We barely mix the flour in fully before adding the M&M’s and chcocolate chips. The reason being that when we stir in the chocolate, that’s when we want to finish mixing the dough. We don’t want to fully mix the dough and then add the candy. The bars at that point would be overworked and tough.
2. Fold in the chocolate chips and M&M’s. By doing this last step by hand, we make sure the candy and chocolate stay intact and that we don’t overmix the dough.
3. Slightly underbake the cookies. By underbaking the cookies–to where they’re just barely set to the touch–we ensure that they stay soft and chewy. By underbaking a little, we also account for any carryover cooking that may occur while the cookie bars are sitting in the pan cooling.

Storing Your M&M Peanut Butter Cookie Bars

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

These bars can also be kept in the fridge to extend their shelf life. Just keep them in an airtight container or wrap them really well in plastic wrap.

Can I Freeze These Bars?

You sure can! They freeze beautifully!

As a matter of fact, I love freezing these bars–especially since this recipe makes a lot.

When I’m ready to devour these bars, I let them thaw in the fridge just until they’re soft enough to bite into. Once they’ve softened, I just eat them cold from the fridge.

As often as I can.

You can also enjoy previously frozen bars at room temp. Just let them thaw completely in the fridge before moving them to the counter to warm up.

Serving Suggestions:

Of course, you can eat these bars as is– and that is by far the best way–but why not live a little? Here are some other ways that these M&M Peanut Butter Cookie Bars can knock your socks off:

• Serve warm with a scoop of vanilla ice cream. Maybe throw in some whipped cream and chocolate sauce for good measure?
• Chop up the bars and stir into some homemade ice cream!
• Top with frosting (vanilla, peanut butter, or chocolate) and additional M&M’s and chocolate chips.
• Cut the bars in half horizontally and fill with either frosting or ice cream to make little cookie bar sandwiches.

Variations and Customizations

This is the fun part! There are so many ways you can tweak the candy or chocolate to totally customize these bars to fit any occasion!

• Change up the colors of the M&M’s to fit the holidays (orange and black for Halloween bars; red and green for Christmas; pink, white and red for Valentine’s Day!)
• Swap out the M&M’s for Reese’s Pieces or Reese’s Peanut Butter Cups to make the ultimate peanut butter cookie bars.
• Trade the chocolate chips for peanut butter chips
• Add some sprinkles!

Pin It For Later!

Some Other Sweet Treats You May Enjoy:

Golden Grahams S’mores Bars

Slutty Brownies

Perfect Cheesecake Squares

Chocolate Covered Popcorn

From Scratch Birthday Cake Cookies

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