325g/3 sticks butter
400g/14 oz plain flour
1/2 tsp salt
for the topping
1 can condensed milk
400g dark chocolate
1/2 tsp corn syrup (or golden syrup) optional, but helps prevent the chocolate from cracking and blooming.
1 Tbsp Maldon Sea Salt (or other flaky sea salt)
• The first thing to get on with is making the caramel. To do this place your unopened can of condensed milk into a large pot cover fully in water. Bring up to a boil and then lower to a simmer, topping up with water as necessary so that the can remains covered for 2 hours. After 2 hours, remove from the water and allow to cool before opening the can.
• For the shortbread, heat the oven to 350F/180C/Gas 4 and line a 20 x 30cm brownie pan with parchment (greaseproof) so that the paper comes up over the sides of the pan on two opposing ends.
• Beat the butter until smooth. Add the sugar and beat until just mixed in. Add the flour and salt and stir until the mixture comes together into a ball. Press evenly into your lined baking tin using something flat (like a cup measure).
• Prick all over with a fork and place in the oven for 30-40 minutes or until the top feels sandy but not too soft and is ever so slightly golden in color. You might want to rotate half way through cooking if you notice it getting darker on one side.
• Remove from the oven and carefully spread over the caramel evenly. Allow to cool.
• Once cool, finely chop the chocolate and melt in a large heat-proof bowl over a pan of barely simmering water. You do not need more than an inch of water in the saucepan and make sure that your bowl doesn’t touch the water. Stir until almost all of the chocolate has melted, then remove from the heat, stir through the corn syrup (this will make the bars easier to cut through) and continue to stir until the remaining chocolate has melted.
• Pour the chocolate over the caramel layer and spread evenly. Sprinkle lightly with Maldon sea salt and chill in the fridge for at least an hour or until the chocolate has set. Once the chocolate layer has set lift the bars out of the pan using parchment that is coming out over the tops. Cut into 32 pieces and store in an airtight container in the fridge. You will find it easier to cut the squares after the pan has sat at room temperature for 30 minutes or so.