In a large mixing bowl, combine cocoa, oatmeal, and coconut. Set aside.

In a medium saucepan, heat the milk, butter and sugar on medium-high heat setting, stirring constantly so that milk does not burn. When the mixture has started to boil and the sugar is blended, remove from heat and fold into the cocoa mixture.

Drop by heaping teapoonfuls onto parchment paper-covered baking sheets, placing them 1/2 inch apart (stir cookie batter occasionally to keep it well blended). Refrigerate for 4 hours and then place cookies in airtight container. Place waxpaper between cookie layers.  

Store in cold room or refrigerator.