½teaspoonblack food coloring paste, optional; see note
Lightly butter an 8X8- or 9X9-inch pan and set aside.
In a heavy-bottomed 4-quart saucepan, combine the water, sugar, condensed milk, corn syrup, and butter. Bring the mixture to a boil over medium heat, stirring constantly with a heat-resistant rubber spatula. Clip a candy thermometer to the side of the pan, ensuring that the tip of the thermometer isn’t touching the bottom of the pan and is inserted at least 1-2 inches into the liquid (or according to your thermometer’s directions).
Continue stirring gently while the mixture boils and cooks, until the caramels reach 242-244 degrees F. If the caramels seem to be scorching on the bottom of the pan, moderate the heat to a lower temperature. You can also test the caramels using a spoon and dropping a pea-sized amount of the hot caramel into cold water. If the cooled piece of caramel is firm but not hard, the caramel is properly cooked.
Remove the pot from the heat and stir in the anise extract, food coloring, vanilla extract and salt. Pour the caramels into the prepared pan and allow to cool completely to room temperature, at least 2 hours.
When cool, remove the sheet of caramels from the pan. Cut the caramels into pieces using a large knife or bench scraper. Wrap each caramel square in a bit of wax paper, twisting the ends to secure.
Anise Extract: ok, let's talk. Anise extract is the classic licorice flavor. It is available in well-stocked grocery stores or online; I bought mine on Amazon (The Star Kay White brand which looks like is currently unavailable) and would encourage you to get pure anise extract not imitation (if there even is such a thing). Anise Oil: I have seen anise oil here and there and I know nothing about it so if you go that route do some research into the potency of the oil. Too much and you'll be hating life and licorice caramels. Extract Amount:I played around with amounts of anise through test batches of these caramels and 2 teaspoons is perfect for my taste but feel free to add more or less depending on how you like the flavor. Food Coloring: also, the black food coloring is optional. Of course it gives the caramels a look to match their flavor but it doesn't add to the flavor, if that makes sense, so if you are opposed to artificial coloring, you can leave it out but by all means, if you are using it, use the paste/gel and not the liquid.