Preheat oven to 250°F (120°C). Line two baking sheets with parchment.
In a clean bowl, whip egg whites to soft peaks.
Gradually add granulated sugar while beating to stiff, glossy peaks.
Fold in cornstarch, vinegar, and vanilla.
Pipe or spoon meringue into three 8-inch circles.
Bake 1.5 hours until crisp. Turn oven off, leave pavlovas inside to cool completely.
Beat heavy cream with powdered sugar until soft peaks form.
Layer pavlovas with whipped cream and lemon curd.
Garnish with fresh berries before serving.