If you’re in the mood for some Halloween-themed baking, then this recipe for Halloween cookies with slime frosting is perfect for you! You will feel like a mad scientist when you inject the fresh chocolatey cookies with oozing green slime frosting. This is a fun recipe to make with your kids before a Halloween party.Jump to Recipe
EASY HALLOWEEN COOKIES WITH SLIME FROSTING
WHAT IS NEEDED TO MAKE SLIME COOKIES?
You will love the delicious chocolate cookie dough base of these Halloween cookies. The dark color is perfect for the holiday, and the rich cocoa flavor balances the sweet slime frosting. These will be a hit with kids and adults alike!
These are all affiliate links, if you purchase (of anything from the site, not just these items) after clicking through, I will earn a small commission. Ads and affiliate links are how I can keep this website running and offer you free tutorials all year. Thank you so much for supporting me and Mad in Crafts!
HALLOWEEN SLIME COOKIE RECIPE
The trick to these treats is melted frosting that is injected right into the chocolate cookies while they are still warm from the oven. Top them off with some scary sprinkles and other decorations to create Pinterest-worthy cookies! They’re easy to make, delicious, and perfectly spooky for the season. Happy Halloween!
EASY HALLOWEEN COOKIES WITH SLIME FROSTINGPrint Pin
- cookie sheets
- Parchment paper
- stand mixer
- microwave-safe dish
- food-safe syringe
For the cookie base –
- 1 cup unsalted butter softened
- ¾ cup sugar
- ⅔ cup brown sugar
- 2 eggs
- 1 t vanilla
- 2 ¼ cup flour
- ⅔ cocoa powder
- 1 tsp baking soda
- ½ tsp salt
For the slime Frosting –
- 1 cup unsalted butter softened
- 3 cup powdered sugar
- 1 tsp salt
- 1 tsp vanilla
- 2-3 Tbsp milk if needed
- Neon green food coloring
- Sprinkles to garnish
- Preheat the oven to 350 degrees. Place parchment on two cookie sheets or spray with non-stick spray. Set aside.
- In the bowl of a stand mixer, combine the softened butter and sugars. Cream together until smooth.
- Add the eggs, vanilla, baking soda, and salt into the stand mixer bowl. Mix well – scraping down the sides and mixing again.
- Add in the flour and cocoa powder and mix well. The mixture will be thick.
- Scoop out a golf-ball sized amount of dough and flatten slightly into a disc. Place on prepared cookie sheets, leaving space between the cookies for spreading during baking. Top with about a teaspoon's worth of sprinkles.
- Bake in preheated oven for 10-12 minutes or until edges are set.
- While the cookies are baking, make the buttercream frosting.
- In the bowl of a stand mixer, combine the softened butter, salt, vanilla, and about half of the powdered sugar. Cream until smooth.
- Add in the remaining powdered sugar and about 1 tablespoon of milk. While it mixes, if you need to add more milk to thin, only add 1 tablespoon at a time until thoroughly mixed.
- Add in the neon green food coloring and whip on high speed for about a minute. Scrape the sides and mix again.
- Transfer about a cup of frosting to a microwave safe dish and heat for about 30 seconds, or until the frosting melts just slightly, and stir.
- Fill the syringe with the melted frosting.
- Once cookies are removed from the oven, immediately inject the melted buttercream into the center of the cookie while it’s still hot and pliable. If you wait too long, the cookie will harden, preventing the frosting from filling the center of the cookie. The frosting should ooze out the cracks and overflow out of the cookie.
- Refill the syringe as needed and fill all the cookies. Follow up with a few more sprinkles, if desired.
- Allow the cookies to cool and for the frosting to set back up. Enjoy!
MORE INFORMATION ABOUT SLIME HALLOWEEN COOKIES
- These slime-frosted cookies are best eaten fresh. If you not serving the cookies on the same day you bake them, you can store them in an air-tight container or food storage bag for three days.
- We used homemade buttercream for the “slime” frosting, but you can swap it out for storebought frosting and it would work just fine.
- You will need a syringe to insert the slime frosting into the cookie. You can pick them up at grocery stores or online.
- If you can’t find a food-safe syringe, you could also use a piping bag or food storage bag to just pipe some slime on top of the cookie instead of injecting it inside the cookie.
- Do not bake the cookie with the slime frosting already inserted – it will make a big mess and the frosting will likely burn!
- You can find Halloween sprinkle mixes in-store or online in the month leading up to Halloween. You can also just use plain orange, purple, and black sprinkles.