Step 1

Combine sugar and water in a medium saucepan over medium heat. Allow sugar to melt and bring to a boil. Let the mixture caramelize and wait for it to turn dark amber in color. Do not stir, swirl pan as needed to promote even caramelization.

Step 2

Sprinkle sugar evenly on the bottom of a medium saucepan set over medium heat. Allow sugar to melt and caramelize, swirling as necessary to promote even caramelization. Do not stir.

Step 3

As soon as the caramel is dark amber in color, reduce heat to low, and gradually add the heavy cream while whisking constantly. Caramel will bubble violently.

Step 4

Stir caramel sauce over low or medium heat until any clumps have dissolved and mixture is smooth.

Step 5

Remove from heat and stir in butter, then vanilla and salt.