Line a baking sheet with parchment paper and set aside.

In a heavy-bottomed saucepan, combine butter, sugar, corn syrup, and salt. Cook over medium heat, stirring constantly until the mixture reaches a boil.

Continue to cook without stirring until the mixture reaches 300°F (hard crack stage) on a candy thermometer.

Remove from heat and stir in vanilla extract.

Quickly pour the toffee onto the prepared baking sheet, spreading it evenly.

Let it cool for about 5 minutes.

Sprinkle chocolate chips over the warm toffee and let sit for a few minutes until melted.

Spread the melted chocolate evenly and sprinkle with chopped nuts.

Allow to cool completely until set, about 1 hour.

Once set, break the toffee into pieces and serve or package for gifting.