1. Melt broken-up chocolate with cream in a double-boiler or over hot water. Remove from heat, stir in butter and, if you'd like, liqueur. Cool, then refrigerate.
2. When chocolate is set, scoop it out using a melon baller or a small spoon. Roll in cocoa powder, confectioners' sugar or crushed nuts. Keep cool until ready to serve.
Yield: About 40 truffles