Preheat oven to 300°F (150°C) and clean your mixing bowl with vinegar-soaked paper towels.

In a sanitized mixing bowl, whisk egg whites and salt on medium speed until soft peaks form (about 2-3 minutes).

Gradually add sugar, about ¼ cup at a time, whisking until thick and glossy.

Whip on high speed for an additional 3 minutes until shiny and stiff peaks form.

Gently fold in the cornflour, vanilla, and vinegar mixture into the meringue.

Dollop meringue onto parchment-lined tray, shaping into a circle with a slight well in the center.

Bake at 250°F (120°C) for 1 to 1.25 hours until lightly browned and dry to the touch.

Turn off oven and let pavlova cool inside for about 3 hours.

Whip cream until soft peaks form and spread into the center of the pavlova, topping with fresh berries.