Beat egg whites until stiff, add cold water and beat again. Add sugar very gradually while still beating.
Slow beater and add vinegar, vanilla and cornstarch.
Place on parchment paper on a greased baking sheet and bake for 45 minutes. Turn off the oven and leave cookies to cool in the oven. NOTE: Don't go opening and closing the oven door. If you must, close the door very carefully. Pavlova is not individual servings, it is of cake-size, decorated with whipped cream and topped with fresh fruit of your choice just before serving.