1.Preheat oven to 150°C (130°C fan-forced). Grease and line two oven trays with baking paper; mark three 8cm-diameter circles on each tray.
2.Combine egg whites, the water, cream of tartar and sugar in medium, deep, heatproof bowl. Stand bowl over medium saucepan of barely simmering water (water should not touch bottom of bowl). Beat with electric mixer about 12 minutes or until mixture is stiff and glossy.
3.Divide mixture among circles; shape into nests. Bake 1 hour; cool in oven with door ajar
4.Make filling by beating cheeses, sifted icing sugar and extract in medium bowl with electric mixer until combined; fold in yoghurt and half the berries. Refrigerate 2 hours.
5.Gently press top of each meringue nest to make a small hollow. Divide filling among meringues; top with berries. Serve dusted with a little sifted icing sugar, if desired.