In a heavy medium sized saucepan, stir together the cream, sugars, and salt. Place the saucepan over medium high heat and bring to a boil, stirring constantly with a wooden spoon. Once the mixture boils, with a heatproof pastry brush that has been dipped in warm water, wash down the sides of the saucepan to remove any sugar crystals that may have formed. Clamp a candy thermometer to the side of the saucepan. Boil the mixture over medium high heat (do not stir) until the temperature reaches 245 degrees F (118 degrees C). (If sugar crystals form on the sides of the pan, wash them down with a heatproof pastry brush that has been dipped in warm water.)
Remove from heat and stir in the vanilla extract. This is when you can dip what you like to coat in caramel, such to make caramel apples.
To make caramel candies, Pour the caramel into your prepared pan and let cool, undisturbed, for at least eight hours, or overnight.
With a sharp knife, (oiled with a tasteless vegetable oil, like safflower), and with a sawing motion, cut into squares or rectangles. These caramels can be stored at room temperature, between layers of wax paper, for several days. Caramels make a nice gift, especially when wrapped in wax paper or cellophane. Makes about 4 dozen caramel pieces.
NOTE: It can be melted back down in the microwave to use as a coating for candies and such. Enjoy.