To make this vegan-friendly, use vegan dark chocolate, and leave out the white chocolate garnish.
Use the leftover chocolate mousse to make truffles. Simply scoop a spoonful of the cold chocolate mixture and roll it in desiccated coconut, cocoa powder, crushed nuts, your favourite blitzed chocolate bar – or anything else you fancy. Decorate with melted white chocolate drizzled on using a cocktail stick, if you like. Then package up in pretty tins and give to lucky friends or family.