Millionaire's Shortbread

Millionaire's Shortbread, also known as a Caramel Slice, is just pure heaven basically! A base layer of buttery shortbread, a middle layer of rich sweet caramel, and then a top layer of yummy chocolate. What more could you want?! I can't think of anyone I know that doesn't like this combination. It's pretty much a guaranteed success whoever you bake it for! This post includes so much information on how to make this tasty bake. Almost every question you could have about making Millionaire's Shortbread is included so make sure to read through this post before you start baking! I've also explained my method of how to cut Millionaire's Shortbread neatly!

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Ingredient Tips & Equipment Information

• Make sure your butter is at room temperature before you start baking the shortbread.
• I used unsalted butter for both the shortbread and caramel layers. You can use salted butter if you like, it won't make it taste salty, instead it will balance out the sweetness. However, I do prefer to use unsalted butter and add my own salt as then I can control the salt levels. You can also use a baking spread, but butter tastes much better in my opinion. It's not that baking spread tastes bad, just that real butter is richer and creamier.
• You must use plain flour (also known as all purpose flour) for the shortbread, self raising flour will make the shortbread rise, which you don't want to happen.
• You must use sweetened condensed milk for the caramel layer, evaporated milk will not work.
• I use granulated sugar for the caramel layer, but caster sugar (also known as superfine sugar) works well too.
• Golden syrup is sold all over the world, so check the international section in your supermarket if you’re not based in the UK. You can also buy it online from Amazon (see link in the recommend equipment and ingredient section). If you can’t get hold of it, light corn syrup is the closest thing to it. You can also use light brown sugar, your caramel will look different and have slightly different texture – but it will still be delicious! Check the recipe notes for details.
• You can use any kind of chocolate for the topping. Milk chocolate is the traditional option, but dark and white chocolate work well too. Pick any chocolate that is good quality and that you like the taste of, I'd advise avoiding cooking chocolate as it doesn't taste great.
• Although I provide cup measurements, I highly recommend weighing your ingredients out using digital kitchen scales. It is the most accurate way to measure ingredients and will ensure the best results. Digital scales are very low cost and can be purchased for around £12 ($16.50) .
• For teaspoon (tsp) and tablespoon (tbsp) measurements, please use measuring spoons and not the type of spoons you eat with. Again this will ensure accuracy and provide the best results.

For the full recipe with measurements, head to the recipe card at the end of this post.

How to make Millionaire's Shortbread

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Start by making the shortbread. In an electric stand mixer, or you can do this by hand, mix the butter and caster sugar together until creamy. Then mix in the vanilla. Finally add the plain flour (and salt if using) and mix until a dough forms.

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Tip the shortbread mixture into a lined tin and press it down with your fingers until it is compact and even. Bake it for 20-25 minutes, or until it is just slightly golden around the edges, then leave it to cool.

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To make the caramel, melt butter, granulated sugar, golden syrup and condensed milk over a low heat until the butter is fully melted and the sugar has dissolved. Turn the heat up to medium and bring it to a gentle boil. While stirring constantly, let it bubble for 5-7 minutes until it is darker in colour and has thickened (this instructions is for gas hobs, for induction hobs, I find that simmering for 10-12 minutes and stirring well to avoid it catching works best). Take it off the heat and mix in the vanilla, then pour it over the shortbread base. Put it in the fridge to set for 2-3 hours or leave on the kitchen counter overnight.

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Take the shortbread and caramel out of the fridge and bring it back to room temperature by leaving it on the kitchen counter for 1-2 hours. Melt the milk chocolate (and white chocolate too if using) either in the microwave, or in a bain marie. Pour the milk chocolate over the top and smooth it out with an angled palette knife. Tap the tin on the work surface a few times to remove any air bubbles. Place the white chocolate into a small piping bag and pipe lines across the milk chocolate. Then using a cocktail stick, run it up and down perpendicular to the lines, to create the feathering effect. Leave to set at room temperature before slicing.

For the full recipe with measurements, head to the recipe card at the end of this post.

What is Millionaire's Shortbread?

It is known by many names: caramel shortbread, caramel squares, caramel slice, millionaire's slice, chocolate caramel shortbread, and Wellington squares. But it always has three layers. A base of shortbread, a middle of caramel and a chocolate top. It originated in Scotland, where the base was made with oats. It is most commonly a small square, but it can also be rectangular or triangular. The name millionaire's is thought to be because the dessert is rich, decadent and high in calories.

What size tin do you need for this recipe?

This recipe is for an 8" or 20cm square tin, it need to have deep sides, at least 2". If you want to use a 9" or 23cm square tin, I would recommend increasing the ingredient amounts by 25%.

What is the best way to line the tin?

I find that greasing the tin very lightly, only just enough to help the baking paper stick to it, then lining with non stick baking paper is the best way to ensure you can remove this bake easily from the tin. You should also leave an overhang of baking paper, about 1" taller than the tin. This is so you can grasp it to pull the shortbread out of the tin.

Do you need an electric mixer to make this recipe?

While it is easier to make the shortbread base in an electric stand mixer with the paddle attachment, you can absolutely make it by hand with a wooden spoon and some elbow grease! For the caramel layer and chocolate layer, no electric mixer is required.

How should it be stored and how long does it last for?

It can be stored at room temperature in an airtight container for 5-7 days (although it never lasts that long in my experience! It gets eaten up too fast!) If the caramel hasn't been boiled for long enough and is too soft, then you may need to store it in the fridge to firm it up. It can last in the fridge for up to 2 weeks.

Can you freeze Millionaire's Shortbread?

Yes! Wrap it well in cling film, or place in a freezer bag or tupperware container. It can be frozen for up to 3 months. It is bet freeze it sliced, then you can easily defrost a piece or two at a time. Place small squares of baking paper between each square to stop them from sticking together. Defrost at room temperature, I usually leave it on the kitchen counter for an hour or so.

How do you slice Millionaire's Shortbread neatly?

This can be one of the most daunting parts of this bake! But I am here to help! The best way I've found to slice it is to firstly make sure that the chocolate has fully set and that it is at room temperature. If the millionaire's shortbread is cold, the chocolate is very likely to crack as you slice it. Secondly, use a very sharp knife that is longer than the shortbread. This means you can slice through it in one motion. If you like you can gently score the chocolate on top to work out the sizes of the squares first. Then, with an even pressure, gently rocking and sawing the knife, push the knife slowly through the chocolate, caramel and shortbread. It's as simple as that! Don't worry if they are not perfectly neat if it's the first time making this recipe, as with everything, practice makes perfect. Sounds like a good reason to make a few more batches right?!

How do you slice Millionaire's Shortbread neatly straight from the fridge or if the caramel is too soft?

You can run into problems if your caramel has not been boiled for long enough, and is therefore too soft. When this happens the caramel can squish out as you slice. Therefore, it may be better to slice the millionaire's shortbread when it is cold. The best way to do this is to use a large sharp knife that's been held under hot running water. Dry the knife off carefully, then gently press it onto the set chocolate. Only cut through the chocolate layer, if you keep pressing down you will smear melted chocolate into the caramel and biscuit layers. Keep wiping the melted chocolate off the knife carefully with a cloth, and putting it back under hot water if it cools down. Always dry the water off before cutting. Once you've cut through the chocolate layer only, pop it back in the fridge for 20 minutes. Remove from the fridge, then cut through the rest of the layers (you don't need to heat the knife this time). And you should get neat clean layers!

Is a gas or induction hob better to make the caramel?

I much prefer using a gas hob to make the caramel for millionaire's shortbread, although it's definitely possible to do on an induction hob too. Gas hobs are better in my opinion because you can control the heat better. You can turn the flame up or down and the heat instantly changes. Whereas with an induction hob you have to wait for the heat to increase or reduce. Even if you only have to wait a few seconds, this can have an impact when it comes to caramel. With a gas hob, it doesn't take very long for the caramel to come to a boil once you increase the heat. I then let the caramel bubble away for about 6 minutes while stirring it constantly. However, with an induction hob it can take several minutes for it to even start bubbling, around 5 minutes. Once it does, it can get too hot very quickly. I find that keeping it on a low heat, only a notch or two above melting heat, so it's just bubbling, but for a longer time works best. On my induction hob (I have a portable one I use for filming my YouTube videos) it takes around 10-12 minutes.

How do you know when the shortbread is baked?

The shortbread usually takes around 25 minutes in a fan oven on 160C. It will be soft to the touch, but this is because it is warm from the oven, so don't mistake this for the shortbread not being cooked. It will also be slightly golden around the edges.

Can you use self raising flour for the shortbread layer?

No, you must use plain flour (also known as all purpose flour) for the shortbread to work correctly.

Can you use a ready made caramel instead?

No, unfortunately if you want this recipe to work you do need to make the caramel from scratch. A shop bought caramel will not be thick enough and won't set like the homemade version. But don't worry, read through this post in full before you start baking and you will have the best chance of success!

Can you use evaporated milk instead of sweetened condensed milk?

No, you must use sweetened condensed milk for the caramel layer. It will not work will evaporated milk.

Do you need a sugar or candy thermometer to make the caramel?

They can be helpful but it is not essential. I never use one, I go off of the amount of time the caramel has been boiling for and how it looks. I boil my caramel for around 6 minutes on a medium heat until it has thickened and darkened in colour. If you have an induction hob, I recommend simmering the caramel for 10-12 minutes. If you want to use a sugar or candy thermometer, you want the caramel to reach 107C/225F.

What is golden syrup and can anything else be used instead?

Golden syrup is a British ingredient made from cane sugar. The main well known brand is Lyle’s, however other brands are available. You can find it in the baking aisle, or near the honey and maple syrup in most supermarkets. It is sold all over the world, so check the international section in your supermarket (grocery store) if you’re not based in the UK. You can also buy it online from Amazon (see link in the recommend equipment and ingredient section). If you can’t get hold of it, light corn syrup is the closest thing to it. However I've not tested this recipe with light corn syrup as this is not an ingredient sold in the UK where I am based. Instead of golden syrup, you use light brown sugar, your caramel will look different and have slightly different texture – but it will still be delicious! Check the recipe notes for more details.

Is granulated or caster sugar best for this recipe?

I use caster sugar (also known as superfine sugar) for the shortbread, and granulated sugar for the caramel. You can swap these around, or use all granulated, or all caster sugar. They will both work.

Can this recipe be made gluten free?

Yes! To make this recipe gluten free you will need to replace the plain flour in the shortbread with a gluten free plain flour blend. You may also like to add ¼ tsp xanthan gum for better texture. All of the other ingredients are gluten free. However, do check all the labels of everything you use in case of cross contamination.

Can this recipe be made dairy free?

To make this recipe dairy free, replace the butter in the shortbread and caramel with a dairy free version. I recommend a dairy free butter block, like Flora Plant or Stork Baking Block. You will also need to use a dairy free condensed milk, Carnation and Nature's Charm are brands I know of. And a dairy free chocolate for the topping. Or you can try my Vegan Millionaire's Shortbread or Vegan Salted Caramel Millionaire's Shortbread recipes.

What is the best kind of chocolate to use for the topping?

You can use any kind of chocolate you like for the topping. I recommend using a good quality one that you like to eat as it does make up a lot of the flavour for this bake.

Do you need to temper the chocolate topping?

Tempering is a process of heating and cooling chocolate to make it stable for making chocolates. Correct tempering results in a lovely shiny finish. While I wouldn't worry too much about exact tempering for this recipe, you do want to avoid over heating the chocolate so that it doesn't bloom (where white streaks appear in the chocolate). I advise heating it very gently and slowly to avoid any blooming.

What can you do with any leftover condensed milk?

If you are using a standard 397g can of sweetened condensed milk, you should not have any leftovers. However if you're using a larger can and you don't want to use the condensed milk in another recipe straight away, you can store any leftover condensed milk in an airtight container in the fridge for 3-4 days, or in the freezer for up to 3 months. It is also delicious stirred into your cup of coffee!!

How many calories are in a piece of Millionaire's Shortbread?

This recipe contains around 417 calories per piece. An online calculator has been used to provide the calorie amount, so there will be slight variations between different ingredient brands. For the full nutritional information check the recipe card at the end of this post.

More tips for making Millionaire's Shortbread:

• To make salted caramel Millionaire's Shortbread add 1 tsp salt to the caramel after it has been boiled and before you pour it into the tin.
• You can also sprinkle the chocolate topping with salt if you like.
• The white chocolate feathering on top is optional, or you could drizzle it round more randomly.

Troubleshooting

My number one tip for getting the best results is to read through this whole page of tips and recommendations before starting, and follow the recipe exactly. If you have any questions about this recipe, or if something went wrong and you need help, have a read of the common issues below, or if you have a different problem please use the comment form below and I will get back to you. You can also get in touch with me on my Twitter, Instagram or Facebook. I'd love to hear from you!

The caramel is grainy

This is because the sugar was not dissolved fully at the beginning of making the caramel. It doesn't affect the flavour at all and the caramel is still totally edible!

The caramel has black burnt flecks in it

This is because the caramel was not constantly stirred while it was boiling. It may also have been boiled on too high a heat. To avoid this happening, turn the heat down slightly and stir the caramel constantly, making sure to scrape the bottom and sides of the pan as you do so. I recommend using a silicone spatula and a heavy duty saucepan for the best results. To remove the burnt flecks from the caramel, pour it through a fine sieve.

The caramel is too soft

This means that the caramel was either not boiled for long enough, or that different ingredients were used (for example condensed milk was swapped for evaporated milk). Boil it for longer next time and make sure you are using the right ingredients. Again, the caramel is still totally edible, but you may want to store it in the fridge to keep it as firm as possible.

The caramel is not dark in colour

As long as the caramel has set well, I wouldn't worry too much about this! It could be down to different brands of ingredients, or just different lighting.

The chocolate is lifting off the caramel

This is due to moisture developing on top of the caramel layer. Make sure it comes fully to room temperature before you add the melted chocolate on top. Also make sure no condensation has formed on top of the caramel, if it does you can remove it by gently dabbing it with kitchen roll before you add the chocolate layer.

Recommended equipment & ingredients

• Mixing bowls
• 8″ Square tin
• Cooling rack
• Kitchen scales
• Stand mixer
• Golden syrup
• Measuring spoons

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