1. Preheat oven 120°C/100°C fan-forced. Mark a 26cm circle on baking paper; then mark an inner circle with a 12cm circle, to form a wreath shape.
2. Beat egg whites with an electric mixer until soft peaks form; gradually add sugar, beating until dissolved after each addition (should take 6 or 7 minutes). Gently fold in NESTLÉ Baking Cocoa and vinegar.
3. Spread meringue inside wreath shape on prepared tray. Using palette knife or spatula, shape sides of meringue. Bake 1 3/4 hours or until dry. Turn oven off, leaving pavlova to cool in oven with door ajar.
4. Just before serving spread cream over pavlova. Decorate with raspberries, blueberries and mint leaves. Spoon NESTLÉ Dark Melts into paper piping bags; drizzle wreath generously with chocolate.