In saucepan mix:

1 tbsp. cornstarch
2 tbsp. cold water

Make paste. Add 1/2 tablespoon boiling water and heat until boiling and clear. Cool. In mixing bowl:

3 egg whites, beat until frothy
6 tbsp. sugar
1 pinch salt
1 tsp. vanilla

Add cooled cornstarch mixture, beat until fluffy incorporated. Spoon over filling, bake at 350 degrees until golden brown 5 to 10 minutes.