Melt together corn syrup and white sugar over low heat. When mixture bubbles, remove from heat and add peanut butter, butter or margarine, and crispy rice cereal.
Grease cookie sheet and put wax paper (also greased) on cookie sheet.
Spread cereal mixture on wax paper.
Mix together 1/3 cup butter or margarine, milk and confectioners' sugar. Stir in cocoa and mix well.
Spread filling on cereal mixture and roll up as for jelly roll. Slice when cool. Store in refrigerator.
