• Line a cookie sheet with wax paper and lightly dust the paper with a little cocoa.
• In a medium mixing bowl, add cocoa, powdered sugar, cream cheese, and vanilla.
• Using an electric mixer, beat until smooth and thick.
• Using a measuring spoon, drop rounded teaspoons of the mixture onto the prepared sheet.
• Using clean hands, roll each portion into a smooth ball.
• Place the tray in the refrigerator and chill for 2 hours, or until firm.

For the Coating (If using):

• In a microwave-safe bowl, melt the semisweet (or milk) chocolate in 20-second bursts, stirring between each, until smooth.
• Using a fork, dip each chilled truffle into the melted chocolate, letting the excess drip off. Return them to the parchment-lined tray. For variety, leave some undipped and roll them in cocoa powder instead.
• Melt the white chocolate and drizzle it over the coated truffles using a spoon or piping bag. Chill again for about 15–20 minutes, until the chocolate shell hardens.
• Store truffles in an airtight container in the refrigerator for up to one week.