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I’ve been baking monster cookies for years, but I knew this classic needed an upgrade. After testing batch after batch, I landed on the perfect chewy version – thanks to rolled oats, a little cornstarch, and a whole lot more chocolate and m&ms. These are the monster cookies you deserve.
Since monster cookies are all about the mix-ins, I didn’t hold back. I increased both the chocolate chips and M&Ms so every bite is loaded. I also prefer using mini M&Ms because they’re speckled throughout the dough instead of clumping together. It gives the cookies a more even texture and pops of color in every bite.
Chewy Monster Cookies Recipe
This isn’t just another monster cookie recipe. It’s a seriously chewy, chocolate-packed upgrade from the original. I’ve been making monster cookies for years, and while the original version was good, I knew it could be better. So I went back to the test kitchen and got to work.
The biggest game-changer was swapping out the quick oats for old-fashioned rolled oats. Rolled oats give these cookies a chewier, heartier texture that holds up beautifully to all the mix-ins. I also added a touch of cornstarch to help create that soft, tender center with just the right amount of structure. It’s a trick I’ve used in other cookie recipes to achieve that perfect bakery-style bite.
How I Improved this Recipe
I tested different cookie dough ball sizes too, from 1 oz (2 tablespoons) to 2 oz (4 tablespoons). While both bake up beautifully, I love the look of the extra-large cookies. They have an irresistible bakery-style presence and the perfect ratio of crisp edges to chewy centers.
I tested this version multiple times, fine-tuning every detail to make sure the texture, spread, and mix-in ratio were just right. The result is a thick, chewy, chocolate-loaded cookie that’s easy for home bakers to pull off and tastes like something straight from a bakery.
How to Make Homemade Monster Cookies
In just a few easy steps, I’ll teach you how to make fresh-baked cookies that are always a hit!
- Prep oven and combine dry ingredients. Preheat the oven to 350º F. In a small bowl, combine the flour, baking soda, baking powder, cornstarch, salt, and oats. Set aside.
- Combine wet ingredients. In a large mixing bowl, cream together the butter, brown sugar and granulated sugar with an electric mixer, for 1-2 minutes. Add in the creamy peanut butter, vanilla and egg, beat again.
- Combine all ingredients. Gradually add in the dry ingredients, mixing on low or by hand just until combined. Add in the mini M&Ms and chocolate chips, mix by hand. The dough will be thick.
- Form cookie dough balls. Use a cookie scoop to form dough balls and place them on a silicone mat lined baking sheet. Press additional m&ms and chocolate chips onto the outside of the balls if desired. I used a 2 Tbsp/1 oz scoop for average sized cookies and a 4 Tbsp/2 oz scoop for extra large cookies.
- Bake and cool. Bake the 2 Tbsp/1 oz size dough balls for 10-13 minutes, bake the 4 Tbsp/2 oz size dough balls for 13-15 minutes or until the edges begin to just turn golden. They will look slightly undercooked, but will continue cooking once removed from the oven. Allow the cookies to cool completely on the cookie sheet.
Tips for the Best Monster Cookies
For perfectly chewy monster cookies, follow my pro tips:
- Properly measure flour: To achieve the right texture, make sure to measure the flour correctly. First, whisk the flour with a fork, spoon or wire whisk. Use a spoon to sprinkle the flour into the measuring cup. Do not tap the cup against the counter, as this will compact the flour. Use the back of a butter knife to level off the excess.
- Room temperature butter: Room temperature butter is key for easier creaming of the butter and sugar and to help achieve that chewy texture we’re going for.
- Use the right peanut butter: I recommend using processed/conventional peanut butter (not natural) creamy peanut butter, like Jif or Skippy, to achieve the right texture. Natural peanut butter is too watery.
- Presentation like a pro: Press extra m&ms and chocolate chips on the outside of the dough balls before baking for that wow factor monster cookie presentation!
Variations & Substitutions
I love classic monster cookies, but if you’re looking to change up the recipe, they are super easy to customize. Here are some ideas:
- Gluten Free Monster Cookies: Be sure to use certified gluten free flour and certified gluten free oats. I have made these cookies multiple times with King Arthur’s Gluten Free Measure for Measure Flour with great success.
- Change the mix-ins: Our recipe calls for 1 cup mini M&M candies and 1 cup chocolate chips. You could swap those for any other mix-in, like:
- Regular size M&Ms
- Reese’s pieces
- peanut M&Ms
- dark chocolate M&Ms
- crispy M&Ms
- shredded coconut
- pecans
- peanut butter chips
- butterscotch chips
- chopped pretzel pieces
- white chocolate chips
- pistachios
- dried fruit
- macadamia nuts
- toffee bits
- Reese’s peanut butter cup pieces
- raisins
- chocolate covered raisins
- mini marshmallows
Storing & Freezing Monster Cookies
Store leftover cookies in an airtight container for 5-7 days. Be sure to let them cool completely first. To keep them soft and moist, add a slice of bread! This trick allows the cookies to soak in the moisture from the bread over time so they don’t dry out.
These cookies also freeze well in a freezer-safe bag or container for up to 3 months. When you’re ready to eat them, thaw them in the refrigerator overnight.
Freezing Monster Cookie Dough
You can also freeze this cookie dough so you have it on hand any time you get the craving for thick monster cookies! To freeze monster cookie dough:
- Drop cookie dough balls onto a silicone mat lined baking sheet. You can place the dough balls close together since you won’t be baking them.
- Place the baking sheet in the freezer until the cookies are frozen solid, about 1 hour.
- Remove the baking sheet from the freezer and transfer the frozen cookie dough balls to a ziplock freezer bag. Separate layers with parchment paper. Label the bag with baking directions.
- Freeze the cookie dough for up to 3 months.
- To bake: remove the dough from the freezer. Pre-heat the oven to 350ºF. Bake for 14-17 minutes. Frozen cookies may need to bake for 1-2 minutes longer.
More Cookie Recipes
- Peanut Butter Chocolate Chip Cookies
- Chewy Chocolate Chip Cookies
- Peanut Butter Oatmeal Cookies
- Chewy Oatmeal Chocolate Chip Cookie
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Monster Cookies
Ingredients
- 1 cup (120g) all purpose flour
- 1 tsp baking soda
- ½ tsp baking powder
- ½ tsp cornstarch
- ½ tsp salt
- 1 ¼ cup (115-124g) old fashion rolled oats
- ½ cup (113g) unsalted butter, room temperature
- ½ cup (107g) brown sugar
- ½ cup (99g) granulated sugar
- ½ cup (135g) creamy peanut butter
- 1 large egg
- 1 tsp vanilla extract
- 1 cup (210g) mini m&ms
- 1 cup (170g) chocolate chips
Instructions
- Preheat the oven to 350º F. In a small bowl, combine the flour, baking soda, baking powder, cornstarch, salt, and oats. Set aside.1 cup (120g) all purpose flour, 1 tsp baking soda, 1/2 tsp baking powder, 1/2 tsp cornstarch, 1/2 tsp salt, 1 ¼ cup (115-124g) old fashion rolled oats
- In a mixing bowl, cream together the butter, brown sugar and granulated sugar with an electric mixer, for 1-2 minutes. Add in the creamy peanut butter, vanilla and egg, beat again.1/2 cup (113g) unsalted butter, room temperature, 1/2 cup (107g) brown sugar, 1/2 cup (99g) granulated sugar, 1/2 cup (135g) creamy peanut butter, 1 tsp vanilla extract, 1 large egg
- Gradually add in the dry ingredients, mixing on low or by hand just until combined. Add in the mini M&Ms and chocolate chips, mix by hand. The dough will be thick.1 cup (210g) mini m&ms, 1 cup (170g) chocolate chips
- Use a cookie scoop to form dough balls and place them on a silicone mat lined baking sheet. Press additional m&ms and chocolate chips onto the outside of the balls if desired. I used a 2 Tbsp/1 oz scoop for average sized cookies and a 4 Tbsp/2 oz scoop for extra large cookies.
- Bake the 2 Tbsp/1 oz size dough balls for 10-13 minutes, bake the 4 Tbsp/2 oz size dough balls for 13-15 minutes or until the edges begin to just turn golden. They will look slightly undercooked, but will continue cooking once removed from the oven. Allow the cookies to cool completely on the baking sheet.
This recipe yields picture perfect delicious cookies every time and has all the good stuff! Our go-to family recipe. We usually make raisin-craisin-chocolate chip Monster Cookies.
Hi Laura! I’m so glad your family loves these! That raisin-craisin-chocolate chip combo sounds delicious!