Special Extra
Sprinkle truffles with crushed peppermint candies and/or multi-coloured sprinkles in addition to, or instead of, the walnuts.
Variation
Coat truffles with icing sugar or unsweetened cocoa powder instead of dipping in the melted chocolate and topping with the walnuts.
Special Extra
Add 1 to 2 tsp. of your favourite extract, such as peppermint, rum or almond; or 1/4 cup of your favourite liqueur, such as orange or raspberry; to the chocolate mixture before shaping into balls.