Soak the gelatine in a bowl with enough cold water to cover them.
Cut the passion fruit in half, take out the yellow pulp with the black seeds and put into a Pyrex bowl with sugar and water. Cover with film.
Microwave on max for 2 minutes then take the pulp to 85°C without boiling.
Add the squeezed gelatine, mix and pour in small semi-circle silicone moulds.
Put in a freezer or blast chiller at -20°C.
Pour the contents of the sachet into a planetary beater, add one litre of cold milk, beat at maximum speed for 5 minutes.
Fill the special moulds three-quarters full, pushing two frozen passion fruit semi-circles into the middle to form a ball.
Close the moulds with their lids and fill with the remaining mousse.
Freeze in a blast chiller for an hour, unmould, glaze with dark chocolate and keep in the freezer.