Caramel Shortbread Bars (Millionaire’s Shortbread)

This Caramel Shortbread Recipe features a buttery shortbread base, gooey caramel, rich milk chocolate, and white chocolate swirls. A classic Scottish treat, it comes together with everyday ingredients and simple steps for an impressive sweet treat that I love to serve for special occasions and holidays. 

If you’re unfamiliar with caramel shortbread, you may know it as caramel shortcake or millionaire’s shortbread. No matter what you call it, this beloved Scottish dessert and sweet treat has become popular across the UK and the United States for good reason. 

Incredibly decadent, the dessert is believed to have originated in Scotland as a twist on traditional buttery shortbread found in recipes like empire biscuits. I grew up eating caramel shortcake, similar to classic jam and coconut sponge, alongside a cup of tea as an afternoon treat when hosting friends.

It’s also a common treat in school lunchboxes or to be eaten during breaktime (recess) and a particular favourite with my kids alongside Mars Bar cake. Truthfully, there’s never a bad time for this recipe!

Ingredients and Notes

Please be sure to scroll down to the recipe card for the complete ingredient list and details.

• Shortbread Base: I use a classic shortbread recipe as the base of the bars. Salted butter adds rich flavour, while caster sugar keeps the texture light and delicate. Then, plain flour brings everything together into a soft dough that bakes into a crisp, crumbly base. I also include vanilla extract to enhance the sweetness and add depth and warmth. 
• Caramel: Sweetened condensed milk creates a signature soft, gooey texture, while golden syrup adds deep caramel flavour. Salted butter and a pinch of salt balance the sweetness, creating a lightly salted caramel flavour that pairs well with the chocolate topping.  
• Milk Chocolate: This is the traditional topping option, adding a smooth, creamy finish, though you can use dark chocolate for a richer taste. I prefer using good-quality chocolate bars rather than chocolate chips for the smoothest consistency and best flavour. 
• White Chocolate: This is optional, but I love using it to create decorative swirls and add extra pops of sweetness that differentiate my caramel shortbread from other recipes.

How to Make This Caramel Shortbread Recipe

Combine the shortbread ingredients. Cream the salted butter, caster sugar, and vanilla extract in a bowl until the mixture is light and fluffy. Then, mix through plain flour until you have a workable dough. 

Shape the base. Transfer the dough to a prepared baking tin, pressing it down to cover the base. I use my hands for this!

Bake. Prick the dough with a fork. This prevents air bubbles and helps create a smooth, flat base. Then place the baking tin in the oven, and bake just until it’s lightly golden. 

Prepare the caramel. Next, combine the condensed milk, golden syrup, sugar, butter, and salt in a pan, and bring the mixture to a boil, stirring continuously. Boil the caramel for five minutes to deepen the flavour. 

Layer, refrigerate and prepare chocolate. Pour the caramel sauce over the shortbread base, and transfer the pan to the fridge to set. In the meantime, break up the milk chocolate and white chocolate, placing the chocolates in separate bowls, and melt using a bain marie or the microwave. 

Add the chocolate topping. Pour the milk chocolate over the caramel, spreading it all the way to the edges. Then, drizzle the white chocolate on top, and use a skewer to run through the chocolate, creating swirls. 

Serve. Chill the caramel shortbread in the fridge, and slice the dessert into bars. Enjoy cold or at room temperature! 

My Top Tips & Tricks

• Line the tin well. Leave a little overhang with the greaseproof paper so you can easily lift the shortbread out before slicing.
• Use room temperature butter for the base. Softened butter creams more easily with the sugar and creates the best shortbread texture.
• Don’t overwork the shortbread dough. Mix just until the ingredients are combined to keep the base tender and crumbly rather than tough.
• Create an even shortbread layer. I break the dough into small chunks and put them all over the tin before pressing down, as I find it the easiest way to press down into an even layer without handling the dough too much. 
• Stir the caramel constantly. Once the caramel ingredients are on the heat, continuous stirring is essential to stop the mixture catching or burning around the edges of the pan. 
• Use a spatula to stir the caramel. This will ensure you are getting right to the edges of the pan, preventing it from burning. 
• Chill before cutting. Giving the bars plenty of time to set in the fridge makes them much easier to cut into neat squares, preventing them from crumbling and falling apart. 
• Slice with a warm knife. Run a sharp knife under hot water, dry it quickly, and gently slice through the chocolate to prevent cracking and create smooth, even bars.