Line a 9x9inch deep square tin with parchment paper.
Melt the butter in a bowl until smooth.
Add blitzed shortbread biscuits to a bowl and add the melted butter, and mix together.
Firmly press the mixture into the bottom of tin and refrigerate for now.
In a large bowl pour the condensed milk, butter, sugar, and golden syrup and melt in 1 minute bursts in the microwave.
Stir the mixture well each time, carefully, until the mixture has thickened. This can take 10-15+ minutes.
The mixture will be ready when it has changed to a slightly darker golden colour, and has thickened to a soft fudge texture!
Pour the caramel onto the shortbread base and leave to set for an hour in the fridge.
Once set, melt the white chocolate and dark chocolate and pour over the caramel – swirl together.
Chill the shortbread back in the fridge for another 1-2 hours until the chocolate has set.
Chop your shortbread into the separate pieces and enjoy!
Notes
This will keep in an airtight container for at least 1 week – if they last that long!
If your caramel is rock solid when you remove it from the fridge, you have slightly over done it. Not to worry though, when you pour the chocolate on, leave it to set at room temperature rather than in the fridge and it should soften the caramel slightly.
**If you struggle to cut your shortbread and tray bakes without the chocolate cracking on top, set it at room temperature rather than in the fridge and it’ll be softer so therefore won’t crack when you cut it!