Place margarine and sugar in a 2-quart pan over low heat. Stir constantly until it reaches a full boil. Boil until it reaches 290 degrees, stirring occasionally.
Add nuts and pour into a 9×13″ buttered pan. Let stand until set.
Place candy bars on warm toffee until melted, then spread to cover all the candy. Sprinkle with the finely chopped nuts. Let cool until chocolate re-hardens, then cut or break into pieces.
