Heat oven to 250°F and arrange a rack in the middle. Trace a 7-8 inch circle on a piece of parchment paper with a pencil or pen. Flip the parchment paper over and place it on a baking sheet. Set aside!
In a dry bowl, beat the egg whites and salt for about 5 minutes or until soft peaks form. With the mixer on high, gradually add in the sugar until stiff and glossy peaks form— about 2 minutes. (This is your meringue!)
Sift the cornstarch into the meringue and pour in the vinegar and vanilla— slowly so you don’t create a ‘dent’ in the meringue. With a rubber spatula, carefully so as to not deflate the egg whites, fold the ingredients into the meringue until no streaks of vanilla remain.
Spread the meringue into the center of your circle and smooth it to the edges to form a rough disk.
Bake until the meringue is firm to the touch and a pale cream color, about 60 minutes. Turn the oven off and leave the oven door slightly ajar, allowing the meringue to cool completely in the oven. Run a thin metal spatula under the meringue to loosen it and carefully place it onto a serving dish; set aside.
Place the cream, sugar, and vanilla in the bowl of a stand mixer fitted with a whisk attachment. Beat on medium-high speed until soft peaks form, about 2 minutes.
Top the baked meringue with whipped and garnish with the fruit of your choice! Serve the pavlova immediately!