Purée the strawberries in a small blender.
Put the strawberry jelly powder in a medium bowl and add 300ml boiling water. Stir in strawberry purée and leave to cool.
Pour the cream into the cooled purée mixture and chill for 10-15 minutes until just beginning to set.
Whisk the egg white to soft peaks, add the sugar and whisk until stiff. Fold into the strawberry mixture and divide between four individual serving dishes.
Chill for 1 hour until set.
The riper the strawberries, the better the flavour in the mousse. This recipe is a good way of using up strawberries that have become a little soft.
