Place the chocolate in a medium bowl and set aside.
Bring the cream just to a boil in a medium saucepan over high heat. Remove the pan from the heat and pour the cream over the chocolate; stir until all the chocolate is melted and smooth.
If you choose to add a liquid flavoring, add it in now. Cover and refrigerate to 2 to 3 hours or until chocolate is firm.
Line a baking sheet with waxed paper. Scoop the chocolate with a tablespoon, small ice cream scoop, or melon-baller and form into 1-inch rounds with the palm of your hands.
Drop the mixture onto prepared baking sheet.
Pass the cocoa powder through a fine sieve or sifter onto a plate. Toss the truffle gently in the cocoa powder or other coating (note variations) to coat evenly.
Place the coated truffles on a plate and continue until are truffles are coated. Refrigerate until ready to serve.
Store in an airtight container for up to 2 weeks. Bring the truffles to room temperature before serving.