Ingredients:

  • 1 cup (225g) unsalted butter, softened
  • 1 cup (200g) brown sugar, packed
  • 0.5 cup (100g) granulated sugar
  • 1 large egg, room temperature
  • 1 tbsp vanilla extract
  • 2.33 cups (290g) all-purpose flour
  • 1 tsp cornstarch
  • 1 tsp baking soda
  • 0.5 tsp fine sea salt
  • 1.5 cups (250g) semi-sweet chocolate chips
  • 14 oz (397g) sweetened condensed milk
  • 2 cups (340g) caramel bits or unwrapped squares
  • 2 tbsp (30g) unsalted butter
  • 0.5 tsp flaky sea salt

Instructions:

  1. Preheat your oven to 350°F (175°C). Line an 8x8 or 9x9-inch square baking pan with parchment paper, leaving an overhang on two sides for easy removal.
  2. In a large bowl or stand mixer, cream 1 cup of softened butter with brown sugar and granulated sugar until pale and fluffy, approximately 3 minutes. Beat in the egg and vanilla extract until well combined.
  3. Whisk together the flour, cornstarch, baking soda, and fine sea salt. Gradually fold the dry ingredients into the wet mixture, then stir in the chocolate chips until a thick dough forms.
  4. Press exactly two-thirds of the cookie dough into the bottom of the prepared pan. Bake for 10-12 minutes until the edges just begin to turn a light golden brown.
  5. While the base par-bakes, combine the sweetened condensed milk, caramel bits, and 2 tablespoons of butter in a small heavy-bottomed saucepan over medium-low heat. Stir constantly until the caramel is melted and completely smooth.
  6. Pour the hot caramel mixture over the par-baked cookie base. Sprinkle with flaky sea salt. Crumble the remaining one-third of the cookie dough over the top of the caramel layer.
  7. Return the pan to the oven and bake for an additional 18-20 minutes, or until the top is golden brown and the caramel is bubbling. Cool completely in the pan before lifting out and slicing into 16 bars.