Go-to Salted Caramel Sauce
Makes 1 cup.
Note: From Martha Holmberg, who likes to take her caramel right up to the precipice, keeping it just this side of bitter. But if you like a sweeter, mellower caramel, stop the cooking a bit sooner. In any case, be sure you have your cream measured and ready to go, because the caramel will continue cooking and darkening, even once you've pulled it off the burner.
• 1 c. sugar
• 1/4 c. water
• 3/4 c. heavy cream or crème fraîche
• 1/2 tsp. kosher salt, or more as needed
• 1/4 tsp. pure vanilla extract, or more as needed
• 1 tbsp. cold, unsalted butter