Ingredients:

  • 1 cup (227g) Unsalted Butter
  • 2 cups (400g) Granulated Sugar
  • 1/2 cup (120ml) Water
  • 1/4 cup (60ml) Light Corn Syrup
  • 1/2 teaspoon Fine Grain Sea Salt
  • 1 teaspoon Vanilla Extract
  • 1 teaspoon Baking Soda (Bicarbonate of Soda)
  • 6 oz (170g) Dark or Milk Chocolate (optional)
  • Coarse Sea Salt for sprinkling (optional)

Instructions:

  1. Preparation: Line a 9x13 inch baking pan thoroughly with parchment paper, ensuring an overhang for easy removal later. Lightly grease the paper surface. Set aside the vanilla and baking soda near the stove.
  2. Initial Combination: In a heavy-bottomed 3-quart saucepan, combine the butter, sugar, water, corn syrup, and salt.
  3. Melting Phase: Heat over medium heat, stirring only until the butter is fully melted and the sugar is completely dissolved (test by rubbing a small amount between your fingers—it should not feel gritty).
  4. Boiling & Temperature Building: Insert a candy thermometer. Increase the heat to medium-high and stop stirring. Allow the mixture to boil vigorously until the temperature reaches exactly 300°F (149°C)—the 'Hard Crack' stage.
  5. The Crucial Addition: Immediately remove the pan from the heat. Quickly stir in the vanilla extract. Then, carefully and swiftly whisk in the baking soda. The mixture will foam up dramatically; this aeration is crucial for the texture.
  6. Pouring: Immediately pour the entire foaming mixture into the prepared baking pan. Do not scrape the sides of the pot. Gently tilt the pan to spread the toffee evenly; avoid pressing or spreading vigorously.
  7. Setting: Allow the toffee to cool completely and harden at room temperature for a minimum of 1.5 hours.
  8. Finishing (Optional Chocolate Dip): Once fully cool and hard, lift the slab using the parchment overhang. Break into 36 medium pieces. If coating, melt chocolate (using a double boiler or microwave). Dip the bottom of each piece, or spread a thin layer over the top, sprinkling immediately with flaky sea salt before the chocolate sets.
  9. Final Set & Storage: Return the finished pieces to parchment paper until the chocolate is fully set, then store airtight.