Super soft and thick peanut butter cookies with oats, chocolate chips, and M&Ms.
“Monster Cookies” are peanut butter oatmeal chocolate chip M&M cookies. For as much as I love peanut butter and oatmeal cookies, it’s quite surprising to see no basic peanut butter oatmeal cookie recipe in my archive. To be honest, the reason I’ve never shared one with you is because it’s taken me almost 3 months to develop one I’m proud enough to publish. Too flat, too puffy, falling apart, rock hard, too dry, and too sweet peanut butter oatmeal cookies have all made their way in and out of my kitchen lately. But not this one. Oh my heavens. I’ve finally found that “perfect” one. I am so excited to show you!
As I mentioned above, “monster cookies” are peanut butter oatmeal cookies stuffed to the brim with colorful M&Ms and chocolate chips. Today’s recipe is unlike most traditional monster cookie recipes though. It’s more like a peanut butter cookie with oats, rather than an oatmeal cookie with peanut butter. Still with me?
Also putting these monster cookies apart from the rest is that they are “soft-baked.” My favorite cookie term. Soft, tender, chewy, and moist in every bite. Quite unlike the crunchy hard peanut butter cookies you are used to. And finally, my version is stuffed with a variety of M&Ms. Peanut Butter M&Ms, classic M&Ms, and mini M&Ms all paid a visit to my monster cookie dough.
Also good to know ahead of time is that my recipe doesn’t make 5-6 dozen cookies like most monster cookie recipes I’ve seen out there that use 3 eggs, 4 cups of flour, 4 cups of oats, 1 pound of butter, etc. Rather, my recipe uses a fair amount of ingredients and yields just 2.5 dozen medium-sized cookies, so they aren’t actually “monster” in size, but feel free to make them larger. Oh and bonus: it can all be mixed up in ONE bowl.
It’s an easy peasy, manageable, and quick recipe. Let’s begin!
You’ll start with the same step a lot of my cookie recipes begin with: cream your butter and sugars together. Like usual, I’m using more brown sugar than white sugar in this cookie recipe. Brown sugar gives the cookies a much softer, chewier, & moist consistency while the white sugar induces spreading. It’s important to use both in today’s recipe.
What I particularly love is that the total amount of sugar is only 3/4 cup in the entire batch. Quite low compared to most other peanut butter oatmeal cookie recipes you’ll find. Next, mix in the peanut butter, egg, and vanilla. The recipe uses a ton of peanut butter. Like I said, it’s more of a peanut butter cookie with oats rather than an oatmeal cookie with peanut butter. Each bite packs intense peanut butter flavor. In my world, the more peanut butter, the merrier.
Next on the list is to add your dry ingredients. Add the flour and baking soda to the same bowl in which you creamed the wet ingredients. No extra dishes to dirty, here. One bowl and you’re done. I love recipes like this!
Finally, mix in the oats. Please use quick oats here. Why? You need the slightly finer size from the quick oats in order to give the cookies a more uniform texture. Quick oats will act more as a binder in this recipe than whole oats would, since the consistency is more powdery and the oats are smaller in size. I actually did not have quick oats at the time, so I ground up my oats in a food processor for a quick 10 seconds to break them down.
I prefer whole rolled old-fashioned oats in my granola and granola bar recipes, but find using quick oats in this cookie recipes works best.
Last up is your add-ins, 3/4 cup of M&Ms and 1/2 cup of chocolate chips. I keep a candy jar of M&Ms on my counter and it currently has a variety of all different kinds. I used a mixture of peanut butter, mini, and regular M&Ms in this recipe. Get crazy! Or just use all regular. The chocolate chips? Just your regular semi-sweet version. I want to try these with white chocolate chips next!
Bake time! That’s right, no dough chilling for this recipe. The dough is quite manageable as is. However, should you bake these cookies with a thinner peanut butter or on a particularly humid day, be sure to chill for up to 30 minutes in the refrigerator. Cookie dough can be testy. Go by how your dough feels. If it’s too sticky, chill for 30 minutes. If not, just bake.
Roll into balls – about 2 Tablespoons of dough each (1 ounce – standard large cookie scoop). Some of mine ended up being a tad smaller than 1 ounce to get 2.5 dozen cookies. Really, you may roll the dough between 1.5 – 2 Tbsp each. I pressed a few mini M&Ms and chocolate chips into the tops of the balls before they baked. To make them look pretty, of course. Bake for a precise 9-10 minutes. Do not overbake. The cookies will appear undone when you remove them from the oven. That is OK, I promise. The cookies will firm up as they cool on the cookie sheet. I allowed my batches to cool for 10 minutes on the sheet before transferring them to a cooling rack.
The cookies spread just slightly while baking, so you’ll need to press them down a bit with the back of a spoon once you remove them from the oven. That’s what gives the cookies their crinkled tops.
Let’s discuss their texture. Wow. I baked these on a Saturday and by Wednesday, they were STILL so soft. Why did they last that long? I forgot I had one sitting around in a little baggie (whoops). So, yes. These cookies remain exceptionally soft for days and days. I also found that their peanut butter flavor is enhanced after day 1, too. Just wait until you taste these!
The oats make them unbelievably chewy, the M&Ms give them a pop of color, and we obviously love the combination of chocolate chips and peanut butter. And I love how thick they are! Even after slightly pressing down after they come out of the oven, the cookies are still so thick and hearty.
In a world where there can never be too many peanut butter cookies, I’m happy to have a peanut butter oatmeal cookie I can use again and again. Especially ones that took me a several batches to develop and perfect. It was worth the wait!
Do you like oatmeal cookies? Peanut butter cookies? Any favorite recipes I need to try?
Soft-Baked Monster Cookies
The best monster cookies ever.
Yield: 2.5 dozen
- 1/2 cup (1 stick or 115g) salted butter, softened to room temperature*
- 1/2 cup (100g) light brown sugar
- 1/4 cup (50g) sugar
- 3/4 cup (185g) creamy peanut butter
- 1 large egg
- 1 teaspoon vanilla extract
- 1/2 teaspoon baking soda
- 1 and 1/4 cups (160g) all purpose flour (are you measuring flour the correct way?)
- 1/2 cup (40g) quick oats*
- 3/4 cup (150g) M&Ms (any size or variety)
- 1/2 cup (90g) semi-sweet chocolate chips
Preheat oven to 350F degrees. Line baking sheet with parchment paper or silicone baking mat.
In a large bowl, using a hand-held mixer or stand mixer with paddle attachment, cream the butter and sugars together on medium speed, about 3 minutes. Mix in the peanut butter, egg, and vanilla (in that order). Scrape down the sides of the bowl as needed. Slowly mix in the baking soda and flour. Do not overmix. Fold in the quick oats, M&Ms, and chocolate chips. If the dough is very soft and unmanageable by hand, chill the dough for 30 minutes before rolling.
Rolls balls of dough, about 2 Tablespoons of dough per ball, onto prepared baking sheet. Press a few extra M&Ms on top for looks, if preferred. Bake for 9-10 minutes - do not bake past 10 minutes. The cookies will appear undone. I too mine out at 9 minutes, which is recommended. Slightly press down the baked cookies with the back of a spoon, since the cookies only slightly spread in the oven. Allow cookies to cool on baking sheet for 10 minutes before transferring to a wire rack. Cookies will firm up as they cool. Store cookies covered at room temperature for up to 1 week. Cookies freeze well.
*You may use unsalted butter in this recipe. If so, add 1/4 tsp salt with the flour.
*Please use quick oats in this recipe. You need the slightly finer texture from the quick oats in order to give the cookies a more uniform texture. Quick oats will act more as a binder in this recipe than whole oats would, since the consistency is more powdery and the oats are smaller in size.
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Let’s talk peanut butter & oats. And see where today’s recipe came from!
Today’s cookies are based off of my Soft-Baked Peanut Butter Lovers Cookies & Rolo-Stuffed Peanut Butter Cookies, among others. These cookies are the same peanut butter cookie base, which is my go-to peanut butter cookie recipe. These cookies do not have oats in them. I tried for weeks and weeks to develop a NEW peanut butter cookie with oats, with terrible results. Then, I came back to my go-to peanut butter cookie recipe and added oats (with a few other slight changes). Simple as that!