Put the raspberries and 1, 1/2 oz of the sugar in a saucepan and add the lemon juice.
Press the berries lightly with the back of a fork. Cook over a medium heat for 10–15 minutes, or until the mixture thickens, then remove from the heat and set aside to cool completely.
Meanwhile, put the cream in a bowl with the remaining sugar and whisk to soft peaks.
Add the yoghurt and rose water to taste and whisk again, then gently fold in the meringues.
Pour in the cooled raspberry mixture and ripple through using the back of a knife.
Spoon the mixture into six 150ml/5fl oz pots and leave to chill in the fridge for at least 1 hour.
Top with extra raspberries, and grated chocolate and serve.
