This is one of the best Pavlova recipes I have ever used. I think that soaking the sugar overnight ensures the sugar dissolves well and provides a crunchy texture.
2 egg whites
2 teaspoons of vanilla
4 tablespoons of boiling water
2 cups of castor sugar
4 teaspoons of white vinegar
2 teaspoons of baking powder
Place egg whites and sugar in a bowl. Soak this overnight. Do not refrigerate.
Beat egg whites for 7 minutes. Add the vanilla, vinegar and water. Beat until stiff (20 minutes). Add the baking powder. Cook in a slow oven for 2 hours.