Monster Mash Cookies

Disclaimer: this post contains affiliate links.

This cookie is made for the chocolate lovers. Two types of cocoa powders wrap up two types of chocolate morsels, and then the outside is coated in m&m’s. Inspired by Gideon’s Bakehouse, this is quite a monster mash of deliciousness.

These cookies are not your typical monster themed cookies. Some monster cookies are a combination of all sorts of delicious ingredients – like pretzels, m&m’s, and chocolate morsels. I’ve wanted to do a monster cookie for some time but I wanted to make it more of a Halloween themed monster cookie – but a simple version that isn’t using royal icing to decorate. I reside in Southern California and have never traveled to Florida, but I HAVE heard of Gideon’s Bake House and all the amazing and unique cookies they make. Taking inspiration from Gideon’s and adding my version of a monster halloween cookie, I can now introduce to you Monster Mash!

These cookies are a combination of two types of cocoa powder, two types of chocolate morsels, and then topped with plain m&m’s. There is A LOT of chocolate going on in this cookie! It is definitely made for the chocolate lovers. This cookie uses both black cocoa powder and dutch cocoa powder – the black cocoa powder gives it that deep black color and the intense chocolate flavor, but the dutch cocoa powder helps offset the bitterness for a softer chocolate flavor. I then added both semi-sweet chocolate morsels and dark chocolate morsels of equal quantities, and then I hand placed the m&ms all around the top and sides of the cookie. The placement of m&ms can be a bit of a painstakingly long effort, but it gives the cookie a fun look without a ton of added work.

Naturally as you bake the cookie and it spreads, so will the gap between the m&ms. So once done baking just have a bowl of m&ms handy so you can stick between the gaps and fill in all those spaces. These cookies do take quite a bit of m&ms since you are covering about a dozen cookies, so I recommend buying the family size bag if you plan to make these! And please be careful when placing after baking – the cookies and baking sheet are hot!

Also, because pulling out the stand mixer and cleaning afterwards is becoming a bit of a pain to me, this is once again a recipe that can be made in one bowl. Yay! These one bowl recipes make clean up so much easier – I don’t know why I didn’t start this sooner! You’ll need a large bowl, a whisk, a spatula, and of course a kitchen scale, measuring cups and spoons and your ingredients. It really is an easy as can be recipe!

Notes Prior To Baking

Cocoa Powders: I used a combination of black cocoa powder and dutch cocoa powder. The black cocoa powder is what helped achieve the dark color in this cookie – no food coloring was used. You can opt to use just the dutch cocoa powder but your cookie will not be dark.

Chocolate morsels: I used both semi-sweet morsels and dark chocolate morsels. The combination of chocolates within one cookie makes for such a delicious and sweet mix. You can of course use just one type of chocolate, or opt to use different chocolate morsels that are your preference!

M&Ms: I used the plain m&ms on this cookie. I don’t recommend using the peanut m&ms or large m&ms because you will use less along the top of the cookies vs. the plain, so it won’t give it as many colors as displayed above. But if you prefer to do that, then go for it!

Refrigerate: don’t skip the refrigeration step! A well developed flavored cookie is due to its opportunity of being left to develop those flavors while in the refrigerator. So refrigerate for at least 12 hours, or up to 24 hours.

Butter: I always use unsalted butter so I can control the amount of salt placed within the recipe. I also allow my butter to sit at room temperature for 30 minutes to 1 hour to allow it to soften just a bit before I place in the microwave. Once I microwave, I only do about 25 seconds so that the butter is not TOO hot and I can move quickly into the next steps rather than allowing the butter to cool.

Storage: These freeze really well! I generally freeze ALL my cookies after baking in freezer safe ziplocks bags. I keep them there for a few weeks and have had no issues. To defrost simply remove the frozen cookie bag and place on your kitchen counter – do not open. Allow to sit for a few hours and come to room temperature, and then you are free to enjoy!

Tools For The Job

kitchen scale

2 tbsp ice cream scoop


parchment paper or silicone baking mat

Sign up for the Newsletter! Be the first to know about new recipes when they go live on the website, exclusive tips & tricks, and giveaways!

Monster Mash Cookies

Sharon Alvarenga
This cookie is made for the chocolate lovers. Two types of cocoa powders wrap up two types of chocolate morsels, and then the outside is coated in m&m's. Inspired by Gideon's Bakehouse, this is quite a monster mash of deliciousness.
5 from 1 vote
Prep Time 45 minutes
Cook Time 13 minutes
Chill Time 12 hours
Total Time 12 hours 58 minutes
Course Dessert, Snack
Cuisine American
Servings 12 cookies


  • 260 g all purpose flour 2 c
  • 220 g unsalted butter, room temperature 1 c
  • 85 g light brown sugar, lightly packed ½ c
  • 100 g sugar ½ c
  • 25 g dutch cocoa powder ¼ c
  • 25 g black cocoa powder ¼ c
  • 2 large eggs room temperature
  • 2 tsp vanilla extract
  • 1/4 tsp baking soda
  • ½ tsp salt
  • 3/4 c semi-sweet chocolate morsels
  • 3/4 c dark chocolate morsels
  • 2 c plain m&ms


  • Place butter in a large bowl and microwave for 25 to 30 seconds until almost completely melted. Remove from microwave and whisk until butter has evenly melted. 
  • Add both sugars and vanilla and whisk until sugars are well dissolved. Add eggs and whisk well to ensure eggs fully incorporate into batter.
  • Add flour, and sift in both cocoa powders to ensure no clumps and even distribution, as well as baking soda and salt. Whisk those dry ingredients with the wet ingredients until fully combined.
  • Toss in both chocolate morsels and use spatula to fold into dough.
  • Line baking sheet with parchment paper or a silicone baking mat.
  • Using a 2 tbsp ice cream scoop, scoop out dough and place on baking sheet, repeating until all dough has been used. Allow at least 2" between cookies to allow for spread.
  • Take the m&ms and begin placing close together along the tops and sides of the cookies. Cover as much surface area as you can but don't forget that you will need to repeat this process after baking since the cookies spread and there will be gaps within the m&ms.
  • Refrigerate cookies for at least 12 hours or up to 24 hours.
  • Preheat oven to 375 F.
  • Remove cookies from refrigerator and place into oven, bake between 13 to 14 minutes. You want to watch for crisp browned edges and the tops slightly underbaked. 
  • Remove from oven and place on wire rack to begin cooling. 
  • Immediately grab the extra m&m's and begin placing between the gaps of the other m&m's. Be very careful since the cookies and baking sheet are still very hot. 
  • Allow to cool completely before enjoying. 
Keyword chocolate cookie, double chocolate cookies, halloween, halloween cookies, m&ms
Tried this recipe?Let us know how it was!


  1. 5 stars
    Chocolate heaven! Seriously delicious and chocolatey

    1. Thank you so much Ana! I appreciate you trying the recipe and I’m so happy you loved it!

Leave a Reply

Your email address will not be published. Required fields are marked *

Recipe Rating