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Hi, I'm Cassie.

Cassia & Co. is a lifestyle blog centered around good food, home decor, musings on life, and the occasional craft project.

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Peanut Butter M&M Cookies

Peanut Butter M&M Cookies

This recipe has been a long time coming, and I am excited to share it with you today. These Peanut Butter M&M Cookies are delicious! I love a good chocolate chip cookie, but there is something irresistible to me about these cookies; they are a bit salty with a crunch of chocolatey goodness from the M&Ms.

The original recipe is from the cookbook Organic and Chic by Sarah Magid. I made a few modifications, particularly to the baking time, as well as adding the M&Ms. We have made quite a few batches of these to get the baking time right because I think they turn out way too crunchy with the time from the original recipe…like break your teeth crunchy. These are not a challenging cookie recipe, but the bake time is very finicky. I’ve included all my notes below to help you get them right.

So, without further ado, here are my beloved Peanut Butter M&M Cookies.

Peanut Butter M&M Cookies


1 stick (1/2 cup) unsalted butter, softened

1 cup crunchy peanut butter

1/2 cup cane sugar

3/4 cup firmly packed dark brown sugar

1 large egg

1 teaspoon salt

1 tablespoon vanilla extract

1 cup all-purpose flour

3/4 teaspoon baking soda

1 - 11 ounce bag of M&Ms (approximately 2 cups)


Preheat the oven to 350º F. Spray baking sheet(s) with non-stick spray, or line with parchment paper. Set aside.

In the bowl of an electric mixer fitted with the paddle attachment, cream the butter, peanut butter, salt, and sugars together on medium-high speed for 3–4 minutes, until light and fluffy. SET THE TIMER AND LET IT MIX THE WHOLE 4 MINUTES. I realized that this is absolutely crucial to getting the cookies to be the right texture. It feels like an eternity so just set the timer and let it mix.

Add the egg and vanilla and mix on medium speed until well combined.

Add the flour and baking soda to the butter mixture and beat on low just to combine. (You can sift it together in a separate mixing bowl and then add it to the butter mixture, but I usually skip that extra step. Don’t tell!)

Add the M&Ms and beat on low just to combine.

Scoop out the dough with a tablespoon and shape into medium-large size balls. Place them about 3 inches apart on the prepared baking sheets.

Use the tines of a fork and press the dough balls down slightly to flatten. You may need to reshape into circles a bit depending on how the M&Ms ended up being distributed in the cookie. (If the fork is sticking a lot, dip the tines in warm water before flattening the cookies. For reference, I’ve never had to do that.)

Bake for 12-14 minutes, until golden brown. SEE ‘BAKING TIME NOTES’ BELOW.

Let cool on the baking sheets for 4 minutes or so and then transfer the cookies to a wire rack to finish cooling. If they are still quite soft and break as you are trying to transfer them, give them another minute or two on the cookie sheet to firm up.


The baking time on these cookies is a bit finicky, and they are hard to tell when they are done. I like to bake them for 10 minutes, check them, and then add 2 minutes and check again. I check them for a golden brown color starting to show around the edges and the middles looking more firm than when I put them in but not fully firmed up.

For my oven and our desired crunchiness level, I like to leave them for 12 minutes. If you want them a little more crunchy, check them at 12 minutes and consider adding 2 more minutes.

For your very first batch, it might be worth just putting 2 cookies on the cookie sheet to test and get a feel for how they bake up in your oven. Set them for 10 minutes and see how they look. Is a golden brown color starting to show around the edges? How do the middles look? Add 2 minutes and check again. If need be, add another 2 minutes until they look done to you. Keep in mind that they will firm up more as they cool.

These would be great for any gathering, but you can also switch up the color of the M&Ms depending on the occasion—red and green for Christmas, pastel for a baby shower or Easter. Especially around the holidays, Target usually has a few different M&M color options available.

I hope you enjoy these cookies as much as I do!

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