These white chocolate mocha bars are an indulgent take on the classic millionaire’s shortbread. This modern twist has a thick layer of buttery shortbread, followed by coffee-infused caramel and a delicate white chocolate topping. Perfect served with a cup of coffee or as a picnic treat, because let’s be honest – who can resist these?

White chocolate mocha bars

My top tips for making caramel:

Caramel can be a pain and sometimes doesn’t act as you want it to! Here are my top tips for making amazing caramel in a saucepan:

  1. Use a good-quality silver saucepan. This ensure the caramel will be heated evenly throughout and prevents any burning on the bottom.
  2. Keep stirring. Make sure you’re continuously stirring to ensure it doesn’t burn. Leaving your mixture to sit over the heat
  3. Keep an eye on it. Caramel can easily bubble over or burn, so make sure you have your full attention on it.
  4. Set a timer. The ultimate boiling period is 8-9 minutes. Make sure it’s bubbling and has thickened up a little.
  5. It’ll thicken as it cools. The sugar in caramel makes for a slightly acidic, sticky ingredient that naturally thickens as it cools. The longer the mixture is allowed to cool in the tin, the thicker it will become.

Want to make these white chocolate mocha bars faster?

If you need to cut down the timings this recipe, you can make the caramel slightly differently by cooking it in the oven – straight on to the biscuit base. The ingredient quantities are slightly different though, so be aware of this. This cuts down the time it takes to make this recipe by 1 hour, as you don’t need to wait as long for the caramel to “set”.

2 x 395g cans sweetened condensed milk
117g golden syrup
1tbsp instant coffee, dissolved in 1/2 tbsp boiling water
80g butter, melted and cooled

  1. Once you’ve made your biscuit base at step 2, place the condensed milk, golden syrup, coffee and remaining 80g butter in a saucepan over medium-low heat and stir until smooth.
  2. Pour the mixture over the cooled biscuit base and bake for 30 minutes until dark golden and the edges are set (the centre will still be soft, but will set as it cools).
  3. Set aside to cool to room temperature before pouring over your chocolate.
White chocolate mocha bars

How to cut your white chocolate mocha bars:

You really want those clean lines, but if you’ve made any type of traybake with a chocolate topping before, you’ll know it’s susceptible to cracking. Here’s how to cut your white chocolate mocha bars to perfection:

  • Remove from the fridge and leave to sit at room temperature for at least 30 minutes. This softens the chocolate layer slightly, making it easier to cut.
  • Use a tape measure to mark out your slices. To get evenly-cut bars, I like to measure my slices 3cm x 7cm and make a small mark on the top of the chocolate. Score the chocolate from top to bottom, side to side as per your markings (don’t press down) so when you go to slice it properly, it’s less likely to crack from the pressure.
  • Use a large chefs knife for the most even slicing. A well-sharpened knife will make for impressive and precise results.
  • Run your knife under boiling hot water and dry with a tea-towel. This helps to melt that top layer of chocolate topping and allows the knife to slide through seamlessly, creating a clean cut.
White chocolate mocha bars

Make a caramelised white chocolate topping instead:

You’ll need:
300g white chocolate (must have a minimum 30% cocoa butter content)

1. Preheat your oven to 125C / 260F, then roughly chop the chocolate and add it to a non-stick rimmed baking tray. 
2. Place the baking tray into the preheated oven for around 1-1.5hrs, removing it every 15 minutes to give it a good stir. I like to use a rubber spatula for this, so you can really scrape it off the tray. The stirring helps avoid it getting grainy and stops it from burning or stiffening up. This is key to making a good caramelised chocolate. 
3. Once the chocolate has turned a rich golden brown colour and is runny and glossy, remove it from the oven and pour 100g over your caramel.
4. Pour the remaining 200g into small microwaveable plastic Tupperware to set completely for another recipe. Pop your bars in the fridge until they’re solid. 

See how I made these over on Instagram!

White chocolate mocha bars

White Chocolate Mocha Bars

These white chocolate caramel slices are made with a buttery shortbread base, delicious coffee-infused caramel and topped with glossy white chocolate!
Prep Time 3 hours
Cook Time 1 hour
Total Time 5 hours
Course Dessert
Servings 15 slices


For the base

  • 200 g plain flour sifted
  • 100 g light brown sugar
  • 150 g butter melted and cooled

For the coffee caramel

  • 1 x 395g can condensed milk
  • 1 tbsp golden syrup
  • 2 tbsp instant coffee dissolved in 1 tbsp boiling water
  • 100 g butter
  • 100 g golden caster sugar

For the white chocolate topping

  • 300 g white chocolate

To serve

  • Chocolate-coated coffee beans


  • Preheat the oven to 170C / 340F. Grease a 20cm x 20cm square tin and line it with baking parchment, leaving a little overhanging on the sides.
  • Sift the flour into a bowl and add the sugar, stirring to combine. Pour in 150g of melted butter and press the biscuit base evenly into the prepared tin, evening out the top with the back of a spoon or your hand. Bake for 25-30 minutes until golden then set aside to cool.
  • Place all the ingredients for the caramel in a large wide nonstick saucepan and bring to the boil, stirring until melted and amalgamated. Reduce the heat slightly so the top is still bubbling nicely all over and cook for 8-9 minutes, stirring frequently. Pour the caramel over the shortbread base and leave to cool for at least an hour until set.
  • Add your chocolate to a heatproof bowl and set it over a saucepan of gently simmering water (don’t let the bowl touch the water). Stir constantly until all the chocolate has melted, remove from the heat and leave to cool for 5 minutes.
  • Pour the cooled chocolate over the caramel, shaking and rotating the pan so the chocolate seeps into the corners and there's one even layer. Chill for 2 hours or until set.
  • Cut slice into squares or bars and scatter with the chocolate coffee beans, if using.
Keyword caramel, chocolate, coffee, millionaire’s shortbread, shortbread, traybake, vanilla, white chocolate

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