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These thick and fudgy Halloween Monster Cookies are so chocolatey with hints of peanut butter, chewy oats, and eyeballs everywhere! They’re easy to make, require no chilling, and are a fun October baking activity.
Pair them with a Spooky Ghost Mocktail, or browse all of my Halloween recipes to find more inspiration.
These are the best cookies you’ll ever taste! They’re thick, chewy, fudgy, and so dang delicious. They’re Halloween monster themed, but they are also monster cookies! You know, oats, peanut butter, and M&M’s, they’re a classic here in the Midwest.
I did amp them up with black cocoa powder so they would be black in color and totally spooky. I also added candy eyes to make them look like little monsters. You can make them for Halloween parties, Trick-or-Treating, or just because you’re craving a festive treat.
If you’re looking for another candy loaded recipe, try my Halloween Snack Mix. It’s coated with green marshmallow slime, so yummy!
Ingredients for Halloween Monster Cookies
Here’s everything you will need to make this cookie recipe. Keep reading for a few important notes.
- Unsalted Butter: Brought to room temperature.
- Sugars: We will use a mixture of granulated sugar and light brown sugar.
- Peanut Butter: Make sure it’s regular ole creamy peanut butter. Natural peanut butters do not hold up in this recipe because of how oily they are.
- Egg: Also brought to room temperature.
- Vanilla Extract
- All-Purpose Flour
- Old Fashioned Oats: These give your cookies a chewy texture. Do not use quick cook or steel cut oats.
- Black Cocoa Powder: For a rich flavor and black color you’ll need black cocoa powder. I do not recommend swapping this out because a different cocoa powder will alter the texture of these cookies.
- Baking Powder and Soda: Using both give our cookies a soft texture and height (so they don’t turn out as a flat mess). Just make sure they’re not expired.
- Salt
- Mini Semi-Sweet Chocolate Chips: Using mini chips add small pockets of chocolate throughout the cookie. They also don’t weight down the cookie (like standard sized chips), especially since we’re adding M&M’s too.
- Halloween M&Ms: Grab a bag of milk chocolate M&Ms in the Halloween colors, they’re festive!
- Candy Eyes: These add the Halloween monster effect, I used Wilton brand.
How to Make Halloween Monster Cookies
1. Make the cookie dough. Cream together the unsalted butter, sugars, and peanut butter. Add the egg and vanilla, then fold in the dry ingredients, mini semi-sweet chocolate chips, and Halloween M&M’s.
2. Scoop and bake the cookies. Scoop and plop the cookie dough onto your baking sheet, and form them into tall piles (pictured below). Bake until the edges are set and the tops no longer glisten.
3. Add eyes to your Halloween Monster Cookies. Remove your cookies from the oven and immediately press the eyes into the cookies. Allow them to cool for 10 minutes before moving over to a cooling rack to cool completely.
Helpful Cookie Tips from Elizabeth
Use the spoon and level method to measure your flour and cocoa powder. Improperly measured ingredients can drastically affect the taste and texture of your cookies. For the flour and black cocoa powder you’ll want to fluff them up using a spoon, scoop into a measuring cup, and then level off with a knife. That will be the perfect amount!
Let the cookie dough rest for super fudgy cookies. There’s something magical that happens when you let the cookie dough rest for 30 minutes to an hour. You don’t refrigerate it, just let it sit. This allows the oats to soften and the black cocoa to take on moisture and become fudgy.
Pile the cookie dough high. If you want thick and chewy cookies like mine, you have to pile up the cookie dough. Rolling or scooping and plopping is not enough, they need to be squeezed to higher heights. During the baking process the cookie dough settles into a thick cookie you don’t need to round out with a drinking glass.
Storing and Freezing Information
Any leftover Halloween Monster Cookies should be stored in an airtight container/ sealable bag. At room temperature they’ll last about 5 days. Or you can store them in the refrigerator for 7 days, and in the freezer for up to 3 months.
Speaking of the freezer, you can also freeze un-baked cookie dough portions (they do not have to be piled high in this case) in a sealable bag for up to 3 months. It’s a great way to prep and get ahead for parties or be prepared when you’re randomly craving cookies. Bake them at the normal temperature, but add a few minutes to make up for the fact they were frozen.
Frequently Asked Questions (FAQ’s)
More Halloween Recipes You Might Like
Halloween Monster Cookies
EQUIPMENT
- stand mixer or hand mixer - paddle attachment
- cookie scoop - medium, 2 tablespoon
- 2 baking sheet - lined with parchment paper
- wire cooling rack
INGREDIENTS
- ½ cup unsalted butter - softened to room temperature
- ½ cup peanut butter
- ½ cup granulated sugar
- ¼ cup brown sugar - packed
- 1 egg - room temperature
- 1 teaspoon vanilla extract
- 1 cup old fashioned oats
- ¾ cup all-purpose flour - measured with spoon and level method
- ¼ cup black cocoa powder - Anthony's, spoon and level method to measure
- ½ teaspoon baking soda
- ¼ teaspoon baking powder
- ¼ teaspoon salt
- ½ cup mini semi-sweet chocolate chips
- ½ cup Halloween M&Ms - plus more for topping
- ¼ cup candy eyes - Wilton
INSTRUCTIONS
- Preheat oven to 350 °F. Line baking sheet(s) with parchment paper and set aside.
- In a small bowl whisk together the old fashioned oats, all-purpose flour, black cocoa powder, baking soda, baking powder, and salt. Set aside.
- In a large bowl add the softened to room temperature unsalted butter, peanut butter, granulated sugar, and brown sugar. Cream together 3 to 4 minutes until it has lightened in color and is fluffy.
- Add the egg and vanilla extract. Combine until incorporated, about 1 minute.
- Add the dry ingredients. Combine until incorporated and the flour has absorbed.
- Add the mini semi-sweet chocolate chips and Halloween M&M's, fold by hand until they are dispersed throughout the cookie dough.
- Scoop and pile portions of cookie dough onto the baking sheet leaving 2 inches of space between each. Add additional Halloween M&M's if desired.
- Bake for 10 to 12 minutes or until the edges are set.
- Remove cookies from the oven and immediately add the candy eyes. Allow them to cool for 10 minutes on the baking sheet before placing them on a wire rack to cool completely.
RECIPE NOTES
- Omit the black cocoa powder to make these classic monster cookies. In it’s place you will want to add an additional 1/4 cup of all-purpose flour for the perfect texture.
STORING INFORMATION
- Room temperature, in an airtight container or re-sealable gallon bag, for up to 5 days.
- Refrigerated, in an airtight container or re-sealable gallon bag, for up to 7 days.
- Frozen, in a freezer safe re-sealable bag, for up to 3 months.
FREEZE & BAKE LATER
- Follow the directions for mixing up the cookie dough, but freeze single portions of cookie dough in a freezer bag for up to 3 months. When you’re ready to bake them, pop them onto a parchment lined baking sheet and bake for 12 to 15 minutes.
Metric conversions are calculated automatically. I cannot guarantee the accuracy of this information.
