Line an 8-inch square baking dish with parchment paper.

In a medium saucepan, mix the sugar, butter, evaporated milk, and salt. Stir together over medium heat until the sugar dissolves.

Increase the heat slightly until the mixture starts to boil. Stir continuously for about 10 minutes until the candy reaches a soft-ball stage (around 235°F).

Remove the saucepan from heat and stir in the vanilla extract.

Carefully pour the hot mixture into the prepared pan and let it cool at room temperature for about an hour until set.

Once cooled, lift the candy out of the pan using the parchment paper and cut into squares.