In a small, heavy saucepan, combine all the ingredients except for the extract and salt, if using.

Cook over medium heat, stirring constantly until the brown sugar dissolves and comes to a boil. Boil about three to five minutes, depending on how thick you want the sauce. (That’s a judgment call; it will be thicker once cooled to room temperature and thicker with refrigeration.) Be careful that the sauce does not burn. If necessary, reduce heat to avoid burning.

Remove pan from heat, add the flavoring of choice, and salt if using, and whisk well. Add in a pinch of salt or up to a 1/4 teaspoon for more of a salted caramel taste.

Serve warm or cold.

Stores several weeks in the fridge. If you have any crystallization, just reheat. If sauce is too thick, reheat slowly. Whisk in additional water if needed.