Monster Cookies
- By Amy Dong
- Updated Dec. 12, 2024
These Flourless Monster Cookies are soft, chewy, and gloriously thick. They’re teeming with oats, peanut butter, chocolate chips, and M&Ms. People absolutely devour these.
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Video: watch us make this Recipe
Why This Recipe Stands Out
Our Monster Cookies are the stuff of legends – they’re big, chewy, and packed with all the good stuff. Here’s why we love this recipe:
- Easy to Make: You don’t need any special equipment or hard-to-find ingredients to make these cookies. Just a trusty mixing bowl and a few basic pantry staples.
- Total Crowd Pleaser: These Monster Cookies were developed for young and old, for munchers from 1 to 101, a lot like our M&M Cookies.
- Thick and Satisfying: The combination of oats, peanut butter, and M&M’s makes for a cookie that’s thick, chewy, and fully satisfying, like these Thick n’ Chewy Oatmeal Dark Chocolate Cookies.
- Gluten Free: These cookies are naturally gluten free, as they need no flour.
Key Recipe Ingredients
- Eggs – The eggs in this recipe act as a binder, holding the cookie dough together and giving the cookies a soft, chewy texture.
- Peanut Butter – Creamy peanut butter not only adds a delicious nutty flavor to these cookies but also helps keep them soft and chewy.
- Butter – Butter is essential for its flavor and for helping the cookies spread slightly while baking, giving them a nice, chewy edge and a soft center.
- Old Fashioned Rolled Oats – We use old-fashioned rolled oats in this recipe, which add a hearty, chewy texture to the cookies and make them more filling.
- M&M’s and Chocolate Chips – The M&M’s and semi-sweet chocolate chips add a pop of color and a boost of chocolatey flavor to these cookies. Plus, they also add a bit of crunch to contrast with the chewy texture of the cookies.
Substitutions And Variations
Here are our favorite substitutions and variation ideas:
- Peanut Butter Substitute: There’s plenty of peanut butter to make all PB addicts happy. But don’t let peanut allergies prevent you from trying these cookies. They can also be made with SunButter as a substitution.
- Different Candy Flavors: Feel free to use your favorite flavor of M&M’s. For this particular batch, I had a bunch of crispy M&M’s in my pantry, so that’s what I used. Peanut, almond, dark chocolate, caramel – any variety of M&M’s would work beautifully in these something-for-everyone monster cookies.
- Seasonal M&M’s: For various occasions, try green and red for Christmas, red, white, and blue for the 4th of July, pink and red for Valentine’s, or pastel for Easter.
- Extra Mix-ins: As long as you stick to the same volume of mix-ins, feel free to throw in your favorite extras. Raisins, nuts, or even pretzels could be a fun addition to these cookies.
Step-By-Step Recipe Instructions
- Combine eggs and sugar in a large mixing bowl. Add salt, vanilla, peanut butter, and butter.
- Stir in M&M’s, chocolate chips, baking soda, and oats.
- Chill the dough for at least 1 hour. Form 1 tablespoon-sized balls and place them on baking sheets. Flatten the cookies slightly and bake at 350F for 7-8 minutes.
For full list of ingredients and instructions, see recipe card below.
How To Prep Ahead
Take a look at our best prep-ahead tips for this recipe:
- Chill the Dough: The dough for these monster cookies needs to be chilled for at least 1 hour or overnight. Take advantage of this by preparing the dough in advance and storing it in the fridge until you’re ready to bake.
- Freeze the Dough: If you want to prepare even further in advance, you can freeze the cookie dough. After mixing all the ingredients, form the dough into a ball, wrap it tightly, and store it in the freezer.
- Thaw Frozen Dough: When you’re ready to bake, let the dough thaw in the fridge overnight and then proceed with forming the dough balls and baking. You can freeze the dough for up to 3 months.
Commonly Asked Questions
Are monster cookies gluten-free?
Many monster cookie recipes contain flour, but this recipe is completely flourless and are gluten-free.
Why do some monster cookies come out dry?
If your monster cookies came out dry, they were likely either over-baked. These cookies should be soft and chewy, so it’s important not to leave them in the oven for too long. Also, make sure you are measuring your ingredients accurately, as excess oats or not enough peanut butter or butter can also result in a dry cookie.
Why do I need to chill the dough?
Chilling the dough helps solidify the fats in the cookies, which leads to a better texture and prevents them from spreading too much while baking.
What type of oats are best for monster cookies?
For the best texture and flavor, we recommend using old-fashioned rolled oats. You can use quick oats in a pinch, but the cookies will have a slightly different texture.
How long do monster cookies keep?
Baked monster cookies can be kept at room temperature in an airtight container for up to a week. If you want to keep them longer, you can store them in the freezer for up to 1 month.
Can I freeze the dough?
You can freeze the raw dough airtight for up to 1 month. Thaw in fridge the night before you’d like to bake.
Did you make this?
Please give us a rating and comment below. We love hearing from you!
Monster Cookies
These Monster Cookies are thick ‘n chewy, soft, and filled with the goodness of whole oats, peanut butter, chocolate, and M&M’s. Every major cookie lovers’ dream come true.
Ingredients
- 3 large eggs
- 2 cups light brown sugar, very tightly packed
- ½ tsp table salt
- ½ tsp pure vanilla extract
- 1 ¼ cup creamy peanut butter, see notes
- ½ cup butter, softened to room temp
- 4 ½ cups old fashioned rolled oats
- 2 tsp baking soda
- 1 ½ cup M&M's
- ½ cup semi-sweet chocolate chips
Instructions
- In a large mixing bowl, combine eggs and sugar. Mix well to combine.
- Add salt, vanilla, peanut butter, and butter. Mix to incorporate.
- Stir in the baking soda and oats. Gently fold in M&M's and chocolate chips.
- Form a ball and wrap tightly with plastic wrap. Chill at least 1 hour or overnight.
- Preheat oven to 350F and live baking sheets with parchment or baking mats.
- Form dough balls about 1 TB in size, and place 2 inches apart on lined baking sheets. Flatten cookies somewhat, as they tend not to spread much.
- Bake 7-8 minutes. Take care not to over-bake. Cookies will set further upon cooling.
Notes
- Different brands of peanut butter contain varying amounts of sugar. If you use a less-sweet peanut butter, you’ll need to add more sugar to the dough. I usually use Skippy Creamy Peanut Butter for best results.
- Be sure to use regular peanut butter that is already creamy and pre-stirred. Some natural peanut butters that have oil separation may not work as well.
- Be careful not to over-bake your cookies. They may seem slightly underdone at the 7-8 minute mark, but they will continue to set as they cool to a soft and chewy texture.
- Feel free to customize your monster cookies with additional mix-ins like chopped roasted nuts, white chocolate chips, or milk chocolate chips.
- If desired, press on additional M&M”s on top immediately after cookies come out of oven.
- These cookies are perfect for making ahead of time. The raw dough can be stored airtight in the refrigerator for up to 5 days or frozen airtight for up to a month.
- This recipe is part of our Easy Desserts Collection.
Nutrition (per serving)
Calories: 210kcal | Carbohydrates: 25.1g | Protein: 4.4g | Fat: 10.3g | Saturated Fat: 4.5g | Cholesterol: 23.5mg | Sodium: 154.3mg | Fiber: 1.9g | Sugar: 16.3g
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