Monster Mash Cookies

There’s something about Halloween baking that always brings out my inner kid. I wanted to create a cookie that captured all the fun, color, and candy chaos of the season, and that’s how these Monster Mash Cookies were born. They’re my Halloween twist on the classic monster cookie: soft, chewy, and packed with peanut butter, oats, and all the good stuff, festive Halloween M&Ms, green KitKats, and sweet butterscotch chips. These cookies feel like digging through your trick-or-treat bag and finding all your favorites in one bite.

Why You’ll Love These Monster Mash Cookies

These cookies are the ultimate Halloween treat; soft, chewy, and loaded with colorful candy fun! Each bite has a perfect mix of peanut butter, butterscotch sweetness, and chocolate crunch from M&Ms and KitKats. They’re festive, easy to make, and guaranteed to be the first thing gone at any spooky get-together. Whether you’re baking with kids or just want something fun and cozy for the season, these cookies bring all the Halloween magic in one bite. 🎃🍪

Ingredients:

Ingredient	Quantity	Purpose
Salted Butter (softened)	1 cup (2 sticks)	Adds richness, moisture, and flavor
Brown Sugar	1 cup	Gives chewiness and a deeper caramel flavor
Granulated Sugar	½ cup	Adds sweetness and helps cookies spread slightly
Creamy Peanut Butter	½ cup	Provides nutty flavor and dense texture
Eggs	2	Bind ingredients and add structure
Vanilla Extract	1 tbsp	Enhances overall flavor
All-Purpose Flour	1 cup	Gives structure and stability
Cake Flour	1 cup	Adds tenderness and a soft crumb
Baking Soda	¾ tsp	Leavening agent for lift and spread
Cornstarch	½ tsp	Keeps cookies soft and thick
Salt	¾ tsp	Balances sweetness and enhances flavor
Old-Fashioned Rolled Oats	2½ cups	Adds chewiness and hearty texture
Butterscotch Chips	½ cup	Add buttery-sweet flavor and texture
Halloween M&Ms	1 cup	Festive color, crunch, and chocolate bursts
Green KitKat Minis (crushed)	½ cup (6 minis)	Festive twist and crunchy texture

How to Make Monster Mash Cookies (Step-by-Step)

1. Prepare your pans:
Line your cookie sheets with parchment paper and set aside.

2. Cream the butter, sugars, and peanut butter:
In a stand mixer fitted with the paddle attachment, beat together softened butter, brown sugar, granulated sugar, and peanut butter on medium-high for 3–4 minutes until light and fluffy.
(This step traps air for a soft, thick cookie texture.)

3. Add eggs and vanilla:
Scrape down the bowl with a spatula. Add the eggs one at a time, mixing until combined. Then add vanilla extract and mix briefly.

4. Mix the dry ingredients:
Add cake flour, all-purpose flour, baking soda, cornstarch, and salt to the bowl. Mix on low speed until just combined and no streaks of flour remain.
(Avoid overmixing to keep your cookies tender.)

5. Add oats and mix-ins:
Stir in rolled oats, butterscotch chips, Halloween M&Ms, and crushed green KitKats until evenly distributed.

6. Shape the dough:
Use a large cookie scoop to portion 24 balls of dough. With your hands, press a bit of extra dough on top of each scoop to make them taller — this helps achieve that thick, bakery-style look.

7. Chill the dough:
Cover the tray with plastic wrap and refrigerate for 30–60 minutes (or up to 24 hours).
If chilling overnight, let the dough sit at room temperature for 30 minutes before baking.

8. Bake:
Preheat the oven to 350°F (175°C). Bake cookies for 13–15 minutes, or until the edges are golden brown and the centers look slightly underbaked (they’ll set as they cool).

9. Perfect the shape:
For perfectly round cookies, gently swirl a glass around each cookie right out of the oven.

10. Cool & enjoy:
Let cookies cool on the tray for 5–10 minutes before transferring to a wire rack. Enjoy your gooey, festive treats!

Common Barriers & How to Fix Them

Barrier	What Happens	How to Fix It
Dough too soft or sticky	Cookies spread too much while baking	Chill dough for at least 30 minutes before baking
Cookies too dry or crumbly	Overbaked or too much flour	Bake until just golden on edges; spoon and level flour when measuring
Cookies not spreading enough	Dough too cold or too much flour	Let dough sit at room temp 10–15 min before baking
Mix-ins clumping together	Uneven distribution in dough	Fold gently by hand or mix briefly on low until evenly spread
Edges brown too quickly	Oven too hot or cookies placed too high	Use middle rack and check oven temperature with an oven thermometer

Tips for Success

Don’t skip chilling the dough! It prevents spreading and creates thick, chewy cookies.
Use room temperature ingredients — it helps everything blend smoothly.
Top before baking: Press extra M&Ms, KitKat chunks, or butterscotch chips into the tops for a bakery-style look.
Slightly underbake: Remove when edges are golden but centers are soft; they’ll finish setting as they cool.
Swirl trick: For perfect round cookies, swirl a glass around them right after baking.

How to Store These Cookies

Keep your Monster Mash Cookies fresh and chewy by storing them in an airtight container at room temperature for up to 5 days. If you want to enjoy them later, they also freeze beautifully. Just place cooled cookies in a freezer-safe bag or container with parchment between layers and freeze for up to 2 months. When ready to eat, let them thaw at room temperature or warm them in the microwave for 10–15 seconds for that fresh-baked softness again.

Customization Ideas & Serving Suggestions

One of the best things about these Monster Mash Cookies is how easy they are to make your own! You can swap the candy mix-ins depending on what you have or what you love most. Try adding Reese’s Pieces, chopped peanut butter cups, or even candy corn for a fun twist. Want a little extra chocolate magic? Drizzle melted white or milk chocolate over the tops once they’ve cooled for a bakery-worthy finish.

When it’s time to enjoy them, serve these cookies with a cold glass of milk, a cup of hot cocoa, or crumble one over a scoop of vanilla ice cream for the ultimate Halloween dessert.

Frequently Asked Questions

Can I use natural peanut butter?
I recommend sticking with creamy, no-stir peanut butter (like Jif or Skippy). Natural peanut butter tends to separate and can make the dough oily or crumbly.

Can I use quick oats instead of rolled oats?
You can, but old-fashioned rolled oats give the cookies that perfect chewy texture. Quick oats will make them a little softer and less hearty.

Do I really need to chill the dough?
Yes! Chilling helps control spreading and gives the cookies that thick, bakery-style look. Even just 30 minutes in the fridge makes a big difference.

Can I freeze the dough or baked cookies?
Definitely! You can scoop and freeze the dough balls for up to 2 months — just bake from frozen and add 1–2 extra minutes to the bake time. Baked cookies can also be frozen for up to 2 months in an airtight container.

How do I make my cookies look like bakery cookies?
Right after baking, take a round glass and gently swirl it around each cookie to create perfectly even edges. For that bakery look, press a few extra candies or KitKat chunks on top while they’re still warm!

And that’s it — your Monster Mash Cookies are ready to make their spooky debut! If you give these a try, I’d love to hear what you think. Leave a comment below, share a photo, or tag me if you bake them — I can’t wait to see your Halloween creations come to life! 👻💚

Monster Mash Cookies