In a large bowl, whisk the yoghurt, 400ml of the milk, honey, rose water, cream and vanilla paste, until it is a smooth runny mix. Heat the remaining 100ml milk till simmering (don’t let it boil). Squeeze the gelatine leaves, so that hardly any water remains in them, and pop these into the hot milk. Stir until dissolved, and then pour the milky gelatine mix into the bowl of mixed yoghurt. Whisk well.