Melt butter in a medium heavy-bottomed saucepan over medium heat. Add the sugar, cream and salt and whisk until well blended.

A flat whisk works great here.] Bring to a very gentle boil and cook for about five minutes, whisking occasionally.

Remove from heat and add one teaspoon of the vanilla extract, stirring to combine. Dip a spoon in the sauce and carefully taste the sauce.

To see if you want to add additional pinches or salt or splashes of vanilla. Tweak it to your taste, whisking well after each addition.

I ended up using a full teaspoon of flaky salt and the listed amount of vanilla to get a butterscotch sauce with a very loud,

Impressive butterscotch flavor but the strength of your vanilla and intensity of your salt may vary.

Serve cold or warm over vanilla ice cream, roasted pears or pound cake. The sauce will thicken as it cools.