• 1/2 tsp. vanilla extract
• Mint leaves for garnish
Preheat oven to 300 degrees. On a piece of baking parchment or foil, trace six 4-inch circles.
Mix a tablespoon of the brown sugar with the cornstarch and set aside. Beat the egg whites and salt until stiff and then add the brown sugar a tablespoon at a time beating until glossy and thick. Add the sugar-cornstarch mix, then fold in the vinegar and vanilla.
Divide the mixture over the six circles and using a spatula or broad, flat knife, work the meringue into bowls (making the sides as high as possible). Bake for 1 hour, turn the oven off and let the shells sit in the oven until it is cool. Remove and gently pry them from the parchment and set on serving plates