3 cups chopped dark chocolate (a little over 1 lb/500g)
Icing (powdered) sugar
Edible flowers or fresh mint leaves, for garnish
Directions
Pour the cream into a large bowl and whip with a whisk or electric mixer until stiff peaks form.
Place the chocolate in a microwave-safe bowl and microwave in 30-second intervals, stirring after each, until all the pieces are melted and the mixture is hot and smooth. (Alternatively, you can place the chocolate in a heatproof bowl and set it over a pot of gently boiling water, stirring regularly until melted and smooth).
While the chocolate is still melted, quickly fold in the whipped cream using a spatula, mixing gently and gradually until the mousse is fluffy and soft. Using a piping bag (or a zip-lock bag with a small hole cut in the corner), pipe the mousse into individual serving dishes and refrigerate for at least three hours, until the mousse is chilled and the texture firm.
When ready to serve, dust each portion with a little icing sugar and decorate with flowers or mint (or however your creative juices inspire you).