Line a baking tray with baking paper or a silicone mat. Scatter the roughly chopped pecans over the base – these will be tucked into the toffee layer.

In a medium, heavy-bottomed saucepan, add the butter, sugar, vanilla, and salt. Place over medium heat and stir gently until the butter has melted and the mixture is well combined. This will take some time so be patient, it's important the heat remains low and the sugar fully dissolves!

Once melted, stop stirring and let the mixture come to a steady boil. Cook until the toffee turns a deep golden colour and reaches the “hard crack” stage (about 150°C on a sugar thermometer). If you don’t have a thermometer, look for the mixture to pull slightly away from the sides of the pan and turn a rich caramel shade. Note: From melting the butter to the hard crack stage, the process takes around 35 minutes.

Carefully pour the hot toffee mixture over the pecans on your prepared tray. Use a spatula to spread it out evenly before it sets.

While the toffee is still hot, sprinkle the chocolate chips evenly over it. Leave them for a minute to soften, then use a spatula to gently spread the melted chocolate into a smooth layer.

Sprinkle the finely chopped pecans over the top of the chocolate while it’s still soft, gently pressing them in so they stick.

Let the toffee cool completely at room temperature until set. Once firm, break it with your hands or cut it into pieces and enjoy!