From Tina and Miranda Jade Turbin of GlutenFreeHelp.info
1. Line a 9-in. square baking pan with parchment paper, ensuring that the paper comes up all sides of the pan.
2. Combine all the ingredients except vanilla in a small saucepan and heat on medium-low. Keep stirring until the sugar is melted and the mixture is uniform throughout. Insert a candy thermometer and keep your spoon and hands off the candy to ensure an accurate reading, watching until the temperature hits 245 degrees.
3. Remove from heat and immediately stir in the vanilla, then pour into the prepared pan. Set pan on wire rack and let it cool until it is room temperature.
4. Remove caramel from the pan and slice into cubes. I recommend wrapping each cube individually in wax paper or plastic wrap.