Heat milk and butter in microwave for 40 seconds, stir until butter melted
Leave it out to cool slightly then add in chocolate, stir until melted
Leave to room temperature, stirring occasionally, until thickened (or you can also leave it in the fridge to speed up process)
Take a tablespoon of firm/thickened ganache, shape into a ball and roll in cocoa powder (or sugar or Reese's for the next balls)
Place into mini cupcake liner and your truffles are ready :)
Serve chilled (from the fridge)!
Enjoy~