Chocolate Pavlova with Berries

Name: Chocolate Pavlova with Berries
Cuisine: European
Ingredients: 6 large egg whites; 1 1/2 (300 grams) cups granulated sugar; A couple pinches of sea salt; 1 teaspoon (5 ml) balsamic or red wine vinegar; 1/4 cup (20 to 25 grams) cocoa powder, the best you have, sifted; 2 ounces (55 grams) semi- or bittersweet chocolate, finely chopped; 1 1/2 cups (355 ml) heavy cream; 2 teaspoons (10 grams) granulated sugar; 1 teaspoon (5 ml) vanilla extract; 4 cups mixed fresh berries; 1 ounce (30 grams) semi- or bittersweet chocolate, to finish