Name: Alien Monster Cookies Mixed With Brownies
Prep time: 10 min
Cook time: 30 min
Total time: 40 min
Ingredients: 2 boxes of gluten free brownies mix (18.3 oz each); additional ingredients listed on the brownie boxes; ⅔ cup creamy peanut butter; 4 tbsp unsalted butter, room temp; ½ cup light brown sugar; 4 tbsp white sugar; 2 large eggs; 1 tsp pure vanilla extract; ⅔ cup 1-to-1 gluten-free flour; ½ tsp baking soda; ½ tsp kosher salt; ½ cup quick oats; ½ cup miniature chocolate chips; ½ cup unsalted sweet cream butter, softened; 2 cup powdered sugar; 2 tsp pure vanilla extract; 2 tbsp heavy whipping cream; neon green gel food coloring; 1 large piping bags, fitted with 1A round tip; 1 cup Halloween sprinkles; 1 package of mini candy eye decorations

Jump to Recipe·Print Recipe

What’s better than a perfectly themed Halloween brownie? A perfectly themed Halloween BROOKIE (a.k.a. brownie and a cookie all in one!), of course! These alien monster cookies mixed with brownies are the best of both worlds and are sure to become a Halloween favorite among your family and friends.

brownies made from a mix with cookie dough inside

There’s just something about the fall that makes me want to head into my kitchen and whip up some tasty treats. And, that’s exactly how these Alien Monster Cookie Brownies were born!

Loosely inspired by the green aliens in Disney and Pixar’s Toy Story, these cookies mixed with brownies are sure to be a delicious treat that is well worth the time spent in the kitchen. They’ve got a thick brownie base, a peanut butter cookie layer, Halloween-themed sprinkles, and giant dollops of frosting on top to create the adorable green alien monsters.

This is a recipe that is perfect for nearly any occasion! Though, I’ll warn you now — you’ll have to eat these up while you can because they probably won’t last long around hungry trick-or-treaters. 😜

Note: For a list of ingredients and instructions, scroll down to the bottom of this post and save the recipe card!

monster cookie brownies lined up on a table

This recipe is perfect for those who are:

Gluten-free
Wheat-free
Fish-free
Shellfish-free
Tree nut-free
Soy-free

Note: I do offer tips on how to make this free of other common allergies below.

cute brownies with green monsters on top

✨ Baking tips

Want to spice these alien monster cookie brownies up even more? Consider adding in grated orange zest, mini marshmallows, or flavored extracts!
These are my favorite mini candy eyeballs to use when making these cookie brownies.
It’s important to have the correct piping tip for the frosting to create those perfectly round alien shapes. This is the one that I always use when making the recipe.
Store any extra alien monster cookie brownies in an airtight container for up to 5 days and pop them in the microwave for a few seconds when you’re ready to serve.

close up of chocolate brownies with sprinkles and little green alien heads on top

✨ How to make and decorate alien monster cookies mixed with brownies

To get started, you’ll need to first follow all of the instructions to make the brownie batter and peanut butter cookie dough separately, according to the recipe.

Once you have these prepared, pour the brownie batter into your baking pan. Then, carefully use a serving spoon to scoop out the cookie dough in small portions and drop them over the brownie batter.

Before you pop them into the oven, be sure to add your Halloween sprinkles on top!

You’ll know when your cookie brownies are cooked when no batter comes up when you insert a toothpick into the center. Once done, let them cool for 30 minutes.

Then, it’s time to decorate! Make the green frosting while you’re waiting for the alien monster cookie brownies to cool, following all of the instructions.

Decorating is simple — just use a piping bag to place some dollops of frosting on top of the brownies and then add your mini candy eyes!

process photo for alien halloween brownies

✨ FAQs

Here are the most common questions I get any time I share this Alien Monster Cookie Brownies recipe. If you have any more questions, drop them for me in the comments below or DM me on Instagram!

Can I make these cookie brownies dairy-free?

Yes! Just use vegan butter in place of the butter when making the brownie batter, cookie dough, and green frosting.

What can I substitute for the eggs in this recipe?

The best substitute for the eggs in this alien monster cookie brownie recipe is applesauce. Though you can also use a special egg substitute like Ener-G’s Egg Replacer or replace the egg with baking powder and milk if that’s all that you have in your kitchen.

Is there a way to make the cookie dough without peanuts?

Absolutely! To make this recipe peanut-free, you could replace the peanut butter with sunflower butter, tahini, and cookie butter, or just forego the ingredient altogether.

Just note that whatever you choose may alter the taste and consistency of the cookie dough.

alien monster cookies mixed with brownies

✨ Looking for more Halloween recipes? Try these:

💜 Follow me on this food journey!

If you are looking for a community that is just as obsessed with Disney as you are, join the rest of the Magical AF Foodies and like our page to always get the inside scoop on Mickey and all of his friends!

Check out the recipe down below 👇