The best Caramel Slice, made with a buttery shortbread base, rich homemade caramel, and a smooth layer of chocolate on top. Also known as Caramel Shortbread, Millionaires Slice, or Millionaires Shortbread, this Scottish tray bake is a firm favourite for bake sales, coffee mornings, or as a nostalgic treat.
If you asked me to make a tray bake to top all of the other tray bakes, Caramel Slice would be the winner. It’s an absolute classic and always a favourite with all ages, made with all the best things you could have in a sweet treat; biscuit, caramel and chocolate!
It seems to come with different names, too. I’ve always known it as Caramel Slice, but it is often called Caramel Shortbread, Millionaire’s Slice, Caramel Shortcake and Millionaire’s Shortbread as well.
Regardless of what name you know it by, the foundations of this tray bake are the same: A shortbread-like biscuit base, a soft layer of sweet caramel and topped with your favourite chocolate(s).
Personally, I like a layer of white chocolate, but more usually, it is a layer of milk chocolate. You can of course mix it up with whatever chocolate you love, or even go for a marble effect with milk and white – the possibilities are endless!
Top Tips for the best Caramel Slice:
(also known as Millionaires Slice and Caramel Shortbread – depending on who you ask!)
• Use a tin with straight edges: If you have a square tin with straight sides (not sloped), it’ll give you those classic, bakery-style slices with neat layers, and you won’t need to try to trim the edges for even slices. This is my go-to baking tin for making all tray bakes.
• Use your favourite chocolate: Traditionally, you’d get Caramel Shortcake topped with milk chocolate, but you can use whatever your favourite chocolate is. You can even use a combination and create a luxurious marbled effect, if you want to be a bit fancy.
• Score the chocolate before it sets: To avoid the chocolate cracking when you cut your slices, score it lightly with a sharp knife when it’s just starting to set, still soft but not wet.
• Cut with a hot knife for clean slices: Run your knife under hot water, dry it off, then slice your Caramel Shortbread. Wipe the blade between each cut for those picture-perfect layers.
More Scottish Baking You'll Love:
Caramel Slice
EQUIPMENT
- 20cm Square Tin ((8-inch))
INGREDIENTS
For the Base
- 250 g Plain Flour (All-purpose Flour)
- 85 g Caster Sugar (Superfine Sugar)
- 170 g Butter or Block Margarine
For the Topping
- 175 g Butter or Block Margarine
- 175 g Soft Light Brown Sugar (Light Brown Sugar)
- 397 g Condensed Milk (Sweetened Condensed Milk) usually one tin
- 4 tbsp
Golden Syrup (Substitutions) - 225 g Chocolate milk, white or dark
INSTRUCTIONS
- Preheat your oven to 180°c (160° fan-assisted ovens, Gas Mark 4 or 350°F) and grease and line a 20x20cm (8-inch) baking tin with greaseproof paper. Set aside.
- In a large bowl, mix the flour & caster sugar before adding the [topping] butter/margarine and rubbing together until it resembles breadcrumbs. Knead the mixture together to form a dough.
- Using your fingers, press the dough into your pre-greased tin, trying to work it into as smooth a finish as possible. Prick holes all over the dough before baking in your pre-heated oven for 20 minutes
- Meanwhile, place the [topping] margarine/butter, [topping] sugar, condensed milk & golden syrup into a pan over a gentle heat until the sugar has dissolved, stirring continuously.
- Bring the caramel mixture to the boil and stir vigorously for 2-3 minutes, until it begins to thicken a little in consistency.
- Pour the caramel over your baked base, ensuring an even finish right into the corners. Leave to cool a little before preparing the chocolate.
- Melt the chocolate (either in short bursts in the microwave or over a bain-marie) before pouring and spreading it evenly over the caramel, ensuring a smooth finish right into the corners.
- Leave to set in the fridge for at least 2 hours, or ideally overnight. Once set, cut into individual squares or slices.
IMPORTANT NOTE:
All my recipes are developed using a digital scale and the metric system (grams and millilitres). Cup measurements are available as a conversion but these, unfortunately, won't always be as accurate. For best results, I always recommend baking with a digital scale.
RECIPE NOTES:
- Storage: Caramel Slice keeps well in an airtight container for up to 5 days. Cut into individual slices before storing in the fridge for firmer layers, or at room temperature if you prefer a softer caramel.
- Freezing: You could freeze Caramel Slice. Once fully set, cut into squares and layer with baking paper in a freezer-safe tub. Freeze for up to 3 months. Defrost in the fridge overnight or at room temperature for a couple of hours before serving.
- Substitutions:
- Condensed Milk: This recipe relies on sweetened condensed milk for the caramel; unfortunately, evaporated milk won’t work as a substitute.
- Chocolate: Milk chocolate is traditional, but dark or even white chocolate works too. Alternatively, you can create a combination and do a fancy marbled effect.
- Butter: You can use block margarine instead of butter if needed, though the flavour will be slightly different. Just be sure to use a high-quality block margarine, not spreadable margarine.
- Golden Syrup: Essential for flavour and texture, but I appreciate it can be tricky to get outside the UK. Have a look at my golden syrup substitutions for all substitution options. Light corn syrup could be used in a pinch, but it won’t be quite the same.
How to make Caramel Shortbread?
Why is it called Caramel Slice, Millionaires Slice or Shortbread?
Why is my caramel runny or not setting?
How do I stop the chocolate cracking when I slice it?
Originally published in March 2018. Updated in June 2025.
14 responses
These bars are just amazing! Mine are not as neat as yours so I will have to make them again (what a shame!) :)
Can I use a 7×7 baking tray?
Thanks.
I cheated and used butter and crushed shortbread biscuits for the base but it worked a treat! Caramel took a bit longer but that’s possibly just my hob settings.
We used to call them chocolate nutncrunch. Does anyone else remeber calling them that?
Please tell me how to get such a smooth chocolate top coat – mine always looks so messy ( a pallet knife would be great but I can’t get it into the pan as the mix doesn’t come all the way up to the top) . Thank you!
Should the base be warm or cooled before adding the caramel layer or does it matter?
Thank you.
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How do you get your melted chocolate smooth as this on top of your slice?
I always just pour it on, never use a knife. I just tap the tin to get it into corners
I have made this twice and it has turned out perfect. It is very good for Xmas gifts. Excellent recipe.
Would it be possible to use your shortbread recipe to form the base of the caramel slice I want a biscuit type base with some crunch. Thanks
Easy to make great to eat.
Excellent recipe Amy thanks for sharing
What size of tin do I use for this recipe please