Step 1: Prepare the Meringue
Preheat your oven to 250°F (120°C). Line a baking sheet with parchment paper and draw a 9-inch circle on the paper as a guide.
In a clean mixing bowl, beat the egg whites with an electric mixer on medium speed until soft peaks form.
Gradually add the granulated sugar, one tablespoon at a time, beating well after each addition. Continue to beat until stiff, glossy peaks form.
Gently fold in the vinegar, cornstarch, and vanilla extract until well combined.
Spoon the meringue onto the parchment paper, spreading it within the circle. Create a slight indentation in the center to hold the toppings.
Step 2: Bake the Meringue
Bake the meringue in the preheated oven for 1 hour and 15 minutes, or until it is dry and crisp on the outside.
Turn off the oven and leave the meringue inside to cool completely with the oven door slightly ajar. This helps prevent cracking.
Step 3: Prepare the Topping
In a mixing bowl, beat the heavy whipping cream with an electric mixer on medium speed until it begins to thicken.
Add the powdered sugar and vanilla extract, and continue to beat until soft peaks form.
Step 4: Assemble the Pavlova
Carefully transfer the cooled meringue to a serving platter.
Spoon the whipped cream into the center of the meringue.
Top with mixed fresh berries, arranging them attractively.