In a medium saucepan over high heat, combine sugar, corn syrup, and water; cook, stirring often, until sugar melts. Cook until temperature reaches 310 degrees (hard crack stage) and mixture becomes amber in color, about 15 to 20 minutes. As mixture cooks, use a wet pastry brush to push accumulated sugar down from the side of pan; be careful not to stir mixture. Now stir in nuts.

Pour carefully onto a baking sheet lined with parchment or Silpat, and spread into a ½-inch layer. Let cool completely (about 30 minutes). Break into pieces. Store in an airtight container.