Classic Fruit Pavlova with Blueberries and Peaches or Whatever - Cooking by the Book

Ingredients

• 4 large egg whites, room temperature
• 1 teaspoon white vinegar
• Pinch of salt
• 1 cup superfine sugar
• 1 teaspoon cornstarch
• 1 cup heavy whipping cream
• 3 tablespoons powdered sugar
• 1 tablespoon pure vanilla extract
• 4 cups of fresh berries, or 4 cups mixed of peach slices and blueberries
• 1 to 2 tablespoons of sugar [optional]