Method

• 1.
  Preheat a barbecue with a lid to the lowest heat (it should be around 150°C).
• 2.
  Using an electric mixer, whisk eggwhites, 1 1/4 cups (275g) sugar and cream of tartar on medium-high speed for 6-8 minutes until stiff peaks. Grease a flameproof baking tray and line with baking paper. Place a wire rack on a separate flameproof baking tray. Spoon meringue onto lined tray and shape into an 18cm circle. Using a palette knife, create swirls and peaks. Place the mint stalks on barbecue grill, then place meringue tray on wire rack and transfer stacked trays to barbecue. Cook with the lid closed for 1 hour 15 minutes or until crisp and slightly charred on the edges. Turn off barbecue and leave meringue in barbecue with lid closed for 30 minutes to cool. Discard mint stalks.

• 3.
  Combine chocolate and 1/2 cup (125ml) pure cream in a heatproof bowl set over a saucepan of gently simmering water (don’t let bowl touch water), stirring until smooth. Cool, then stir through sour cream and remaining 1 1/2 cups (375ml) pure cream. Chill until ready to serve.
• 4.
  Place one-quarter of the raspberries, remaining 2 tbs caster sugar and 2 tbs water in a bowl and mash with a fork.
• 5.
  Using an electric mixer, whisk cream mixture to soft peaks, then spoon on top of pavlova. Top with raspberry puree, watermelon, remaining raspberries and mint leaves. Serve immediately.