Preheat the oven to 350°F and line a 9x13-inch baking pan with parchment paper and set aside.
Mix the flour and icing sugar together. Then cut in the butter (using a pastry cutter). The mixture should be crumbly.
Press the crust into the prepared baking pan.
Bake the crust for 20 minutes then allow the crust to cool completely.
Caramel
To make the caramel, combine the butter, brown sugar, sweetened condensed milk, and corn syrup in a heavy-bottomed saucepan. Cooking at medium temperature, bring the mixture to a boil, stirring constantly.
Allow the caramel to boil for 2 minutes, then reduce the heat to a simmer and continue cooking for another 10 to 15 minutes, stirring constantly. The mixture should begin to pull away from the sides of the pot.
Remove the pot from the heat and stir in vanilla and salt.
Pour the caramel over the cooled shortbread crust. Allow this layer to cool in the fridge for at least an hour before adding the chocolate topping.
Ganache
Place the chocolate chips in a glass bowl with a lid, set aside.
Heat the heavy cream until it is just simmering.
Pour the heavy cream over the chocolate chips, cover with the lid, and let sit undisturbed for 5 minutes.
Stir the cream and chocolate together until smooth. Stir in the vanilla.
Carefully pour the ganache over the caramel layer.
Chill the bars until set then slice into squares.
Notes
Storage Instructions: These squares will keep for up to 2 weeks at room temperature - just make sure they are stored in an airtight container. They can be frozen for up to 3 months.
These bars seem decadent, can I cut them into smaller pieces? YES! These bars are RICH and oh, so delicious so you can actually cut them into 18 bars, then cut those all in half to get 36 thinner bars if you want a smaller serving size!
I only have unsalted butter - can I use this instead? Yes! Just add ½ teaspoon of salt to the crust and ½ teaspoon of salt to the caramel.
Should I keep these in the fridge? These are best stored at room temperature. There is no need to refrigerate and if you do keep them in the fridge, the chocolate will look dull instead of shiny.
How can I make the squares cut neatly? I find that it helps to get a neat cut if you run the knife under hot water before slicing the bars.
I don’t have any heavy whipped cream - can I use milk to make the ganache? Yes! In this recipe, you could use 3 Tablespoons of melted butter mixed with ½ cup of milk to melt with the chocolate for the ganache.