Mix sugar and corn starch in 1 1/2 Qt heavy bottom saucepan.
Stir in corn syrup, water, salt and butter.
Cook over medium heat, stirring constantly, until mixture boils and sugar is completely dissolved.
Continue cooking, without stirring, until temp on candy thermometor reaches 260 F. If you dont have one; take a small amount and drop it into very cold water, it should form a ball and hold its shape when removed from the water.
Remove from the heat and add the vanilla.
Grease the sides and bottom of a 9X9 pan. Pour mixture into pan and let sit until cool enough to handle.
Pull and fold in half. Continue pulling and folding until it has a satin finish and light color.