Chop chocolate into pieces and melt in a double boiler. Stir in butter and icing sugar.
Remove from heat and stir in coconut and vanilla.
Beat cream until it thickens, but not so that it is stiff. Fold into the chocolate mixture and mix well. Chill.
Once the mixture is quite solid, scoop out portions using a spoon and roll into balls.
For the coating, break the chocolate into pieces. Melt with milk and vanilla in the ouble boiler, stirring to a smooth consistency.
Line a baking tray with greaseproof paper. Dip the truffles in the chocolate using a fork or a wooden skewer. You will have to work quickly while the covering is still runny. Place the truffles on the greaseproof paper and allow the chocolate to set. Place in little paper cases and store in the fridge.