Monster Cookies

Monster Cookies are loaded with peanut butter, oats and M&Ms. They are so soft, tasty, and definitely kid approved.

I absolutely adore monster cookies. I could eat them all day, every day. I mean who doesn’t love a cookie loaded with peanut butter and M&Ms?! I know I sure do… For a tasty twist try out Gluten Free Monster Cookies and Dark Chocolate Monster Cookies. 

A stack of Monster Cookies

A Kid-Favorite Cookie Recipe

I think what I love most about these is how easy they are to make. They literally take a few minutes to whip up and while the dough rests (to allow the oats to absorb the excess moisture), you can preheat your oven and wash up the dirty dishes. Plus they’re always a huge hit, especially with kids. Our little one is as smitten with these as I am. Go figure 🙂

Because these cookies have a good amount of peanut butter and oats in them, they’re pretty soft. Make sure you don’t overbake them or they’ll dry out. And when you take them out of the oven, leave them on the sheet for a few extra minutes to firm up. That way you don’t risk the chance of them cracking or even worse, breaking completely apart.

Next time you’re in the mood for cookies but want something different, you’ve gotta give these monster cookies a try! I think you’re going to love them! And make sure to check out this recipe if you’re looking for a gluten-free version.

How to make monster cookies - stirring dough in a mixing bowl

How to Make Monster Cookies

WET INGREDIENTS. In a large mixing bowl or the bowl of a stand mixer, beat together the peanut butter, butter, sugars and vanilla extract. Add the egg and egg yolk, mix just until combined.

DRY INGREDIENTS. In a medium mixing bowl, whisk together the oats, flour, salt and baking soda.

COMBINE. Gradually add the dry ingredients to the wet ingredients. Mix until a soft dough forms. Fold in the M&Ms with a spatula.

REST. Let the cookie dough to stand for 15 minutes to allow the oats to absorb any excess moisture.

BAKE. Meanwhile preheat oven to 350 degrees, line baking sheets with parchment paper or baking mats. Using a standard size cookie scoop (#40 or 1.5 tbsp.) scoop balls of dough and place onto prepared sheets, gently pat to slightly flatten. Place in the oven and bake for 10-12 minutes, taking care not to over bake.

COOL. The cookies will look soft, but allow them to cool on the sheets for 5 minutes before transferring them to a wire rack to cool completely.

Recipe Tips

Best oats to use? We like quick oats or old fashioned oats, don’t use steel cut oats. You will want a soft oatmeal texture as opposed to a stiff and hard oatmeal. The steel cut oats won’t get enough moisture by just being incorporated into the cookie mix.

Other mix-ins: You could always try adding Reeses Pieces, dark chocolate M&M’s, chocolate chips, or peanut butter chips. Basically any type of chocolate chips or m&ms would be a good substitution/addition. Make sure the total amount of mix-ins doesn’t exceed 2 cups.

Monster Cookies

Tips, Tricks, and More Cookies

Why are my Monster Cookies falling apart? You need to let the cookies sit on the cookie sheet for about 5 minutes before transferring them to a cooling rack. If you move them too early, they will fall apart. 

If they are still falling apart after they’ve cooled completely you could’ve added too many mix-ins and not enough binders. This means that next time you should add less chocolate chips and m&ms and more eggs/butter/peanut butter.

STORE your cookies in a bag or tupperware at room temperature. You don’t want your cookies to dry out, so it’s best to keep them in an airtight container of sorts. To double-ensure that they don’t dry out you can store them in a tupperware container with a piece of bread. The bread will get stale while your cookies stay fresh and soft!

FREEZE either the baked cookies, or the cookie dough!

  • To freeze your cookie dough, roll into balls, pre-freeze them on a cookie sheet and then place them in a freezer safe airtight bag. They will last about 3 months. At this point you can bake them normally but you may have to add a couple of extra minutes. 
  • To freeze baked cookies, let them cool completely before placing them in layers in a freezer safe bag with pieces of parchment paper between them. To eat them, take them out of the freezer and bring them to room temperature before eating. You can also warm them slightly in the microwave.

For more family favorite cookie recipes, try:

Monster Cookies

Monster Cookies Recipe

Monster Cookies are loaded with peanut butter, oats and M&Ms. They are so soft, tasty, and definitely kid approved.
5 from 4 votes
Pin Rate
Course: Cookies
Cuisine: American
Prep Time: 20 mins
Cook Time: 10 mins
Total Time: 30 mins
Servings: 18 cookies
Calories: 305kcal
Print Recipe

Ingredients

  • 1/2 cup peanut butter - creamy or crunchy
  • 1/2 cup unsalted butter - melted
  • 1/4 cup granulated sugar
  • 3/4 cup brown sugar
  • 2 tsp vanilla extract
  • 1 egg
  • 1 egg yolk
  • 2 cup quick oats - not old-fashioned
  • 3/4 cup all-purpose flour
  • 1/2 tsp salt
  • 1/2 tsp baking soda
  • 1 1/2 cup M&Ms - regular, mini, or mix of both
  • 1/2 cup chocolate chips - OR peanut butter chips OR chopped peanuts(optional)

Instructions

  • In a large mixing bowl or the bowl of a stand mixer, beat together the peanut butter, butter, sugars and vanilla extract. Add the egg and egg yolk, mix just until combined.
  • In a medium mixing bowl, whisk together the oats, flour, salt and baking soda. Gradually add the dry ingredients to the wet ingredients. Mix until a soft dough forms. Fold in the M&Ms with a spatula.
  • Let the cookie dough to stand for 15 minutes to allow the oats to absorb any excess moisture.
  • Meanwhile preheat oven to 350 degrees, line baking sheets with parchment paper or baking mats.
  • Using a standard size cookie scoop (#40 or 1.5 tbsp.) scoop balls of dough and place onto prepared sheets, gently pat to slightly flatten. Place in the oven and bake for 10-12 minutes, taking care not to overbake. The cookies will look soft, but allow them to cool on the sheets for 5 minutes before transferring them to a wire rack to cool completely.

Notes

-You can easily add peanut butter chips, chocolate chips or chopped peanuts for added flavor and texture!

Nutrition

Serving: 18g | Calories: 305kcal | Carbohydrates: 39g | Protein: 5g | Fat: 15g | Saturated Fat: 8g | Cholesterol: 37mg | Sodium: 155mg | Potassium: 99mg | Fiber: 2g | Sugar: 27g | Vitamin A: 235IU | Vitamin C: 1mg | Calcium: 46mg | Iron: 1mg

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About the Author

Natalie

Wife, mother, baker and photographer. Recipe developer & author of Life Made Simple. A self-professed peanut butter lover and fond of anything that involves pumpkin, cookie dough, or sprinkles

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Comments:

  1. Yum, these look delicious! I know my nieces and nephews would love them. They are crazy about these types of cookies.

  2. There’s absolutely nothing wrong with these pictures. And monster cookies are one of the best kinds of cookies ever! YUM.

  3. I have always been a huge fan of monster cookies. How do you get yours so perfectly shaped? They look amazing and I bet taste great!!

  4. These are some gorgeous cookies. I think the M&M’s make these cookies very exciting and quite pretty! I could take a dozen of those guys off your hands and a glass of milk. 🙂

  5. 5 stars
    These are always a hit with my family. The flavor and the color is so fun. The perfect combo!

  6. 5 stars
    Delicious!! We are making cookies weekly around here & these are one of our favorites to make! Love the m&m’s with the peanut butter & oats! Everyone loves them!