1.Place yoghurt in a sieve lined with a muslin or absorbent piece of cloth. Place sieve over a bowl. Cover; refrigerate overnight.
2.Combine honey, cream and vanilla bean in a medium saucepan; stir over low heat, until honey dissolves. Remove from heat.
3.Meanwhile, sprinkle gelatine over the measured water in a small heatproof jug; place in a small saucepan of simmering water, until gelatine dissolves. Stir gelatine into honey mixture. Cool until lukewarm; remove vanilla bean. Stir yoghurt into honey mixture, until combined.
4.Beat egg whites until firm peaks form. Add sugar; beat until dissolved. Fold egg whites into honey and yoghurt mixture. Pour mixture into six 3/4-cup (180ml) serving glasses. Cover; refrigerate about 3 hours, or until set.
5.Meanwhile, place measured water, honey and muscatels in a small saucepan; bring to the boil. Simmer, uncovered, 5 minutes, or until syrup has thickened. Cool.
6.Serve mousses topped with honey muscatels and drizzled with syrup.
The flavour of this mousse will be influenced by the type of honey used. Muscatels are large dried grapes on the stem, available from gourmet food stores and some health food stores. If whole vanilla beans are unavailable, you could substitute 1 teaspoon vanilla bean paste. Not suitable to freeze. Suitable to microwave.