Ingredients:

  • 450g Unsalted Butter (cold, cubed)
  • 200g Caster Sugar
  • 600g Plain Flour
  • 1 tsp Salt (for shortbread)
  • 225g Unsalted Butter (for caramel)
  • 300g Light Brown Sugar (packed)
  • 397g can Sweetened Condensed Milk (full fat)
  • 60ml Golden Syrup (or light corn syrup)
  • 1 tsp Flaky Sea Salt (for sprinkling)
  • 500g Good Quality Dark Chocolate (minimum 60% cocoa solids), chopped
  • 50g Unsalted Butter (for topping)
  • 1 tbsp Vegetable Oil (for topping)

Instructions:

  1. Preheat oven to 350°F (175°C). Line a 13 x 9 inch (33 x 23 cm) baking tray completely with parchment paper, leaving an overhang.
  2. For the shortbread base, combine the cold, cubed butter and caster sugar in a mixer until just combined. Sift in the flour and salt. Mix on low speed until the mixture resembles coarse breadcrumbs.
  3. Tip the mixture into the prepared tray. Press firmly and evenly across the base using the flat bottom of a glass. Bake for 30–35 minutes, or until the edges are lightly golden brown. Let cool slightly.
  4. For the salted caramel, melt the butter, brown sugar, condensed milk, and golden syrup in a heavy-bottomed saucepan over medium heat. Stir until the sugar is dissolved.
  5. Bring the mixture to a rolling boil without stirring too vigorously. Boil for exactly 5–7 minutes, stirring gently but constantly to prevent scorching. The mixture should thicken noticeably.
  6. Immediately pour the hot caramel evenly over the warm shortbread base. Sprinkle the top lightly with flaky sea salt. Refrigerate for at least 1 hour to allow the caramel to firm up.
  7. For the chocolate topping, combine chopped dark chocolate, butter, and oil in a heatproof bowl set over simmering water (bain-marie). Stir gently until completely smooth and glossy.
  8. Pour the melted chocolate over the chilled caramel layer, tilting the tray gently to ensure an even coating to the edges.
  9. Return the tray to the refrigerator for a minimum of 2 hours, or until the chocolate is completely set and snaps when lightly pressed.
  10. Use the parchment overhang to lift the entire slab out. Use a long, sharp knife dipped in hot water and wiped dry between cuts to slice into neat squares.