In large microwave-safe mixing bowl, microwave caramels, margarine and water at HIGH 3 minutes or until melted and smooth, stirring after each minute.
Add KELLOGG'S COCOA KRISPIES cereal and cashews. Stir until well coated. Add 1/2 cup white chocolate chips, stirring until combined.
Spread mixture into 13 x 9 x 2-inch pan coated with cooking spray. Let stand about 2 minutes. Sprinkle the remaining white chocolate chips over the mixture and press evenly into the pan. Cut into 2-inch squares when cool.