After dinner minty chocolate mousse

Method

1. Pound the caster sugar and mint leaves using a mortar and pestle until you have green-coloured sugar. Set aside.
2. Break up the chocolate and put into a heatproof bowl with the coffee. Sit the bowl over a pan of barely simmering water (making sure they don’t touch) until just melted. Stir, remove from the heat and cool.
3. Whip the cream with about one-third of the mint sugar until soft peaks form. In a clean bowl, whip the egg whites until soft peaks form. Add the remaining mint sugar a little at a time until soft and glossy. When the chocolate has completely cooled, fold in the stiff egg whites until smooth. Then fold in the mint cream until smooth and no traces of white are left.
4. Spoon into 6 glasses and chill for at least 1 hour until set. Decorate each with a mint leaf