Mixed Nut Brittle

Place nuts in two greased 15-in. x 10-in. x 1-in. baking pans. Bake at 350 degrees F for 10 minutes or until warm. Set aside and keep warm. Meanwhile, in a large heavy saucepan, combine sugar, corn syrup and water. Cover and bring to a boil over medium heat. Uncover and cook until a candy thermometer reads 290 degrees F (soft-crack stage). Remove from the heat; stir in nuts, butter, vanilla and salt. Quickly spread into a thin layer on baking pans. Cool completely; break into pieces. ');