Perfected Millionaire’s Shortbread (Caramel Squares)

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Hi Bold Bakers!

Conas atá tú Bold Bakers? With St.Patricks Day fast approaching I wanted to share a recipe for a treat that is really popular in Ireland called a caramel square (aka Millionaire’s Shortbread). It has a layer of shortbread, layer of caramel, and milk chocolate on top. I have very fond memories of these growing up so I’m happy to be able to share an authentic recipe with you.

Where Does Millionaire’s Shortbread Come From?

Caramel shortbread squares originated in a 1970’s Australian Women’s Weekly magazine. However, it is believed that the name actually came from Scotland. There are many names for this treat: caramel squares, millionaire’s bars, caramel shortcake, or caramel slices.  

If you think about it, Twix bars are also a Millionaire’s Shortbread!

How to Make Millionaire’s Shortbread

Millionaire’s Shortbread has 3 parts (or layers) to it: Shortbread, Caramel, and Chocolate. It’s easier to breakdown how to make each of these components separately because making the final dessert is just an assembly of them all. For the sake of clarity, though, here’s how you make Millionaire’s Shortbread:

1. Make the shortbread.
2. Let it cool.
3. Make the Caramel.
4. Spread the caramel on top of the shortbread – then let it set.
5. Melt your Milk Chocolate.
6. Spread your milk chocolate on top of the other two layers, and let this set as well.
7. Cut and serve!

The assembly is very simple, so let’s take a look at making the layers!

[ Get my Top 5 Recipes for St. Patrick’s Day! ]

How To Make Shortbread

Classic shortbread is typically made with flour, butter, and sugar in a 3:2:1 ratio. Shortbread is called such because the ratio of butter that is cut into the flour “shortens” the gluten strands resulting in a moist yet crumbly cookie.

Shortbreads are incredibly easy to make because it just calls for the creaming of the butter and sugar then mixing in the flour until a dough forms. 

1. Preheat the oven and butter/line your baking pan.
2. Cream together the butter and sugar — to make this easier, make sure the butter is at room temperature.
3. Add the flour and salt, mix into a dough.
4. Press the dough into your baking pan, making sure it’s even for thorough baking!
5. Bake until lightly browned on top.

Is There An Easy Way To Make Caramel?

This method of cooking caramel seems to be the easiest way to make a caramel because it doesn’t involve caramelizing sugar with the use of a candy thermometer. Caramelizing sugar could be quite tricky because the sugar could crystallize and ruin the whole batch of caramel. This alleviates that kind of caramel risk. 

Here’s how to do it for these caramel squares:

1. Put your cans of Sweetened Condensed Milk and Butter in a heavy-bottomed saucepan.
2. On medium-low heat, bring to a simmer while whisking constantly.
3. Continue this process until the mixture thickens, turns an amber-hue, and you’ve been at it for 15+ minutes. Whisk the whole time so nothing sticks to the bottom of the pan to avoid lumps.
4. Pour it over the shortbread to cool at room temperature for a few hours.

If you’d prefer a different caramel, find out how in my How to Make Caramel guide.

Adding The Chocolate

Luckily, you don’t have to make the chocolate. You just need to gently melt it in the microwave or over a bain marie before pouring it over the cooled caramel to also set at room temperature. I use milk chocolate in this recipe. It is sweeter, but that’s part of what makes these squares so “rich.”

Storing Millionaire’s Shortbread

Store in an airtight container at room temperature. No need to store these guys in the fridge. The flavor of each layer is sooo much better when at room temperature.  

Millionaire’s Shortbread lasts surprisingly long. At a minimum, I would say 5 days, but I have stored them for up to 10 days. Honestly, they have a tendency to ‘evaporate’ as the days go by so you won’t have to worry about this.

Gemma’s Pro Tips for Millionaire’s Shortbread

• It’s really important to use room temperature butter to make the shortbread as it needs to be creamed really well
• When making the caramel, stir constantly! Since there’s milk involved, a constant stir will prevent burned caramel on the bottom of the pan
• Cut the squares when the chocolate is set but not fully hardened. This way you won’t crack the chocolate when cutting. 
• When you butter and line your pan, leave some parchment overhanging on the sides so it will be easier to remove the bars. 
• Use a clean, warm, and dry knife when cutting the bars. A clean knife will prevent the layers from running into each other. A dry knife will prevent the caramel from sticking to the knife. 

Get More Recipes!

• Homemade Twix Bars
• Homemade Granola Bars
• Clotted Cream Caramels

Don’t forget to buy a copy of the Bigger Bolder Baking Cookbook so you can get my Irish Shortbread Recipe!

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