Cookie

The Australian Cookies That Are Better Than Thin Mints (Yes, We Said It!)

December  2, 2014

The Mint Slice is an Australian supermarket staple, a cookie second only to the Tim Tam (which you’ve probably heard about). It’s very similar to a Thin Mint—both have crisp dark chocolate cookie bases and a thin covering of dark chocolate.

The kicker with the Mint Slice, however, is the layer of mint icing nestled between the crispy base and the chocolate coating; that icing is what takes these cookies to a whole new level. 

Even though these are definitely a year-round treat in Oz, their holiday appeal is undeniable. They go so perfectly with a cup of tea, coffee, or hot chocolate, and their peppermint scent is completely Christmas-y. Mint Slice cookies have great make-ahead potential, too. Not only can the raw dough be stored in the freezer for up to two months, well wrapped, but the assembled cookies freeze beautifully, too.

These are a little time consuming to put together, but they’re very simple. The cookies are slice and bake, and the mint icing simply stirs together. In fact, if you’re not too worried about potentially getting melted chocolate everywhere, these could be a great project to do with kids.

Not only are these perfect for gift giving, cookie swaps, and even keeping little ones entertained, they're also the perfect solitary treat for every and any moment that you can sneak between the holiday bustle of wrapping presents, shopping, baking, and watching marathons of cheesy movies (which is not to say these wouldn't go really well with The Santa Clause, You’ve Got Mail, and Elf).

Homemade Mint Slice Cookies 

Makes 20 cookies 

For the cookies:

4 ounces butter, softened
1/2 cup granulated sugar
1 egg
1/4 cup cocoa powder
1 cup all-purpose flour

For the filling and the coating:

1 1/2 cups powdered sugar
1/2 teaspoon peppermint extract
4 ounces milk chocolate
2 ounces dark chocolate
1 tablespoon coconut or vegetable oil

Cream together the butter and sugar until the mixture is light and fluffy. Scrape down the bowl, add the egg, and continue beating until the egg is incorporated and the mixture lightens in color. Add the cocoa powder to the egg mixture and beat until there are no lumps. Finally, fold in the flour until it is all incorporated. You should expect the dough to be very soft.

Turn it out onto a piece of baking paper, roll it into a log about 1 1/2 inches thick, and wrap the dough. Place the log into the freezer to chill for at least 30 minutes. Preheat the oven to 350° F (180° C) and line two baking sheets with baking paper. 

 

When the dough is finished chilling, take it out of the freezer and slice it into 1/2-inch pieces; you should get about 20 rounds. Place the cookies onto the baking sheets and bake for 10 minutes. Remove the cookies from the oven and leave them to cool completely on the baking sheets. 

To make the mint filling, simply stir together the powdered sugar, the peppermint extract, and 1 tablespoon of water. The mixture should be very thick, like the texture of playdough. Take a scant teaspoon of the mint filling and use it to top each cookie, patting and smoothing it with your fingers so that it covers the top but stops shy of the edge of the cookie.

To coat the cookies, melt the chocolates and the coconut (or vegetable) oil together in the microwave in short bursts, stirring well between each until you have a smooth mixture. Once the chocolate mixture has cooled slightly, dip each cookie in the chocolate, coating it completely. 

Set the coated cookies on a rack over a piece of foil or parchment paper to drip and set. Once they're set, these should be stored in the fridge, where they'll keep well for at least a week. They also freeze beautifully for up to a month in an airtight container, and they even taste great straight out of the freezer. 

See the full recipe (and save and print it) here.

Photos by Sarah Coates

19 Comments

Beth100 July 16, 2016
I'm old enough to remember when Girl Scout thin mint cookies had a layer of mint icing between the cookie in the chocolate coating. This went away sometime shortly after my scouting days were over. They were the best!
 
judy December 19, 2015
I think the only addition I would make is to put some mint in both the cookie dough and the chocolate as well. I never think that there is enough mint in these mint baked goods recipes. So I'm always increasing the amount. I like the idea of crushed peppermints on top for the holidays. Thanks for the recipe. I have tried several GS substitutes. None quite make it, and even recent year GS TMs are not minty enough.
 
Keena H. December 10, 2015
I've made these many times, but in a slab. Bake the cookie in a shallow baking dish, top with peppermint then chocolate. Chill and cut into squares. Much easier.
 
Alyssa October 22, 2015
Question- when you say milk chocolate and dark chocolate what exactly do you mean?
 
Birdie M. December 14, 2014
although these look better
 
Author Comment
Sarah C. December 14, 2014
Haha, thanks Birdie! Homemade does have the edge...but I'm no stranger to those storebought cookies!
 
Birdie M. December 14, 2014
You can find Mint Slice biscuits at World Market stores (right next to the Tim Tams ;)
 
Mandi J. December 4, 2014
The only thing that can beat an Arnott's choccy bikki is a homemade one! Looking forward to giving these a burl, though with the current temps we've got Down Under, they'll have to stay hidden in the freezer! And Mint Slices are great to do the Tim Tam Slam with!
 
Helen R. December 3, 2014
Going to make these, don't by GS cookies because they're full of icky ingredients, among other reasons. I think I will sprinkle the tops with crushed peppermint candy, because that will be festive :) and yummy.
 
Author Comment
Sarah C. December 3, 2014
Great idea!
 
cynthia |. December 3, 2014
These sound SO GOOD. And that last photo is insanely gorgeous!!
 
Author Comment
Sarah C. December 3, 2014
Thanks Cynthia! I'm trying to break into hand-modelling.
 
CarlaCooks December 3, 2014
You're the next J.P. Prewett!
 
Author Comment
Sarah C. December 3, 2014
This is the best comment I've ever seen.
 
Lori W. December 2, 2014
Really looking forward to trying these. I'm also gah-gah over the dual saucer cup porcelain pictured. Do you happen to know the brand?
 
Author Comment
Sarah C. December 3, 2014
Hey Lori, it's a Crown Devon 'Stockholm' demitasse cup and saucer. It's a vintage series of china that I'm totally obsessed with - I'm psyched you like it too!
 
mungo December 3, 2014
I think they're gorgeous too! New obsession, engage...
 
Annabel Y. December 2, 2014
My husband and I used to live in New Zealand and Mint Treats were a staple in our household. Thank you for this - we have been missing them desperately!
 
Author Comment
Sarah C. December 2, 2014
That's awesome! So glad to help, Annabel!