Grease a 9 inch pan. Sprinkle half of almonds or pecans in bottom, melt butter in a heavy saucepan, add remaining ingredients except chocolate, cook stirring constantly and allowing to boil vigorously 7 to 10 minutes until golden brown (290 degrees on a candy thermoneter) carefully pour into pan, place candy bars on toffee, when melted spread evenly, sprinkle with remaining nuts. Refrigerate to set chocolate, break into bite sized pieces.