Line 12 x 18 in. cookie pan with parchment paper. Generously grease paper with butter; set aside. Meanwhile, over medium-high heat, combine sugar and water in medium saucepan, stirring until sugar is dissolved. (Use pastry brush dipped in water to wash sugar crystals down on sides of saucepan.) Continue cooking, without stirring, 20-30 minutes until sugar mixture turns deep amber in color and Candy Thermometer registers 300ºF. (Carefully watch sugar mixture, as it can quickly turn from amber to dark brown.)