Homemade soft caramels

Butter a 9x13 pan very well, into the sides and corners, so the caramel does not stick; set aside.

Melt the unsalted butter in a saucepan over medium heat.

Pour in the sweetened condensed milk, then add the brown sugar and the corn syrup.

Stir with a rubber spatula, scraping the sides and bottom, and bring to a simmer over medium heat. Do not raise the heat above medium; stir the entire time.

Cook to the soft ball stage, 235 to 245 F on a candy or instant-read thermometer. It tends to stall around 220, so wait for it to creep up. Too long gives a firm caramel that sticks in the teeth; too short stays liquid.

Without a thermometer, drip some caramel into very cold water: it should form a ball that hardens, then flattens a little once out of the water. One that stays a total ball will be a hard caramel.

Remove from the heat and immediately stir in the salt and vanilla extract until the salt disperses.

While it bubbles, pour into the prepared pan. Cool at room temperature at least two hours, until completely cool.

Cut into little squares and wrap each in a piece of wax paper, twisting the ends.