Makes about 3 dozen truffles
Method
In a heavy saucepan, over low heat, melt chips with butter.
Stir in cocoa until smooth.
Add condensed milk and vanilla.
Cook and stir until thickened and well blended, about 4 minutes.
Remove from heat.
Chill until firm enough to handle. Shape into 1 inch balls.
Roll in desired coating.
Chill until firm. Store, covered in refrigerator