Cook first 3 ingredients in a medium-size heavy saucepan over medium heat, stirring contantly, until mixture starts to boil. Boil without stirring 5 minutes or until a candy thermometer reaches 310º. Add peanuts, and cook 2 to 3 minutes or to 280º. (Mixture should be golden brown.) Remove from heat, and stir in butter and remaining ingredients.
Pour mixture onto a metal surface or into a shallow pan. Allow to stand 5 minutes or until hardened. Break into pieces.