Set up a bain marie (double boiler). I place a stainless steal bowl over a small saucepan of simmering water.
Add chocolate chips, heavy cream to bowl and stir slowly until all the chocolate chips are melted.
At this point, you can add flavorings such as vanilla, bourbon, etc.
Refrigerate until the ganache is set.
Roll into balls and roll in cocoa powder.
Notes
Butter: I have found I do not need to use the butter when I use the Choc Zero Dark chocolate chips. You may find you need to add the butter to other brands