Peanut Butter M&M Cookie Bars

These simple and fun peanut butter cookie bars filled with M&Ms are here to satisfy your sweet craving!

Peanut Butter M&M Cookie Bars

We spent a weekend in Vegas this month and since we had the kids with us, we made a stop at the M&M Factory. And you guys, sooo much candy came home with us. We’ve been slowly working our way through it, and it was only a matter of time before some M&Ms ended up in my baking.

I borrowed the recipe from my favorite peanut butter chocolate chip cookies [1], swapped the chocolate chips out for M&Ms, spread the dough into a baking pan because I was feeling lazy, and these bars were born. They couldn’t be simpler or more perfect for a quick homemade treat.

The kids of course loved them, and so did the adults!

Peanut Butter M&M Cookie Bars

Peanut Butter M&M Cookie Bars

baking tip:How parchment paper can make baking easier

For cookies, biscuits and scones: Line sheet pans with parchment paper before using. Prevent sticking without adding any extra grease and cleanup is as easy as throwing away the parchment.

For cakes: Line the bottoms of your cake pans with parchment paper and then either grease and flour, or coat with baking spray. You’ll never have a cake stick in your pan again!

For bars and breads: Line square or rectangular pans with parchment so that there’s a few inches of overhang on either side. When your baked good is ready to serve, use that overhang as a handle to lift it out of the pan. Then transfer to a cutting board and slice. No more messing up a slice trying to dig it out of the pan!

Peanut Butter M&M Cookie Bars

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Peanut Butter M&M Cookie Bars

These simple and fun peanut butter cookie bars filled with M&Ms are here to satisfy your sweet craving!


  • 1/2 cup (113 grams) unsalted butter, softened to room temperature
  • 3/4 cup (200 grams) smooth or crunch peanut butter
  • 1 1/4 cup (265 grams) light or dark brown sugar
  • 1 teaspoon vanilla extract
  • 2 large eggs
  • 2 cups (240 grams) all-purpose flour
  • 3/4 teaspoon baking soda
  • 3/4 teaspoon coarse salt
  • 1 cup (210 grams) M&M candies (I used mini)


  1. Preheat oven to 350 degrees F. Grease a 9-inch baking pan and line with parchment paper [4].
  2. With an electric mixer beat the butter, peanut butter, and brown sugar until light and creamy. Add vanilla extract and eggs, mixing after each.
  3. Add the flour, baking soda, and salt and mix until just combined. Add the M&Ms.
  4. Spread the cookie dough into the prepared pan and bake until edges are golden brown and middle is puffed, 25-30 minutes.
  5. For best results and prettiest slices, let cool completely before slicing. Once cool, use parchment paper to lift bars out of pan and transfer to a cutting board. Cut into 16 equal pieces.

Have you tried this recipe?

I’d love to hear about it! Leave a comment below, send me an email [5], or take a photo and tag it on instagram [6] with #completelydelicious [7].

URLs in this post:

[1] peanut butter chocolate chip cookies:

[2] More Baking Tips »:

[3] Print Recipe:

[4] line with parchment paper:

[5] send me an email:

[6] instagram:

[7] #completelydelicious: