1 (9-inch) pie shell, baked
1 1/4 c. sugar
6 tbsp. cornstarch
2 c. water
1/2 c. lemon juice
3 eggs, separated
3 tbsp. butter
1 1/2 tsp lemon extract
2 tsp. vinegar

PRELIMINARIES: Adjust oven rack to middle position and preheat oven to 350 degrees.

PROCEDURE: Mix sugar and cornstarch together in top of double boiler. Add the water and stir to combine. In a separate bowl, combine egg yolks with lemon juice and beat until smooth; add to sugar mixture. Cook until thick over boiling water, about 25 minutes. Add butter, lemon extract and vinegar; stir thoroughly. Pour into a baked 9-inch pie shell and let cool. Cover with meringue and brown in preheated 350 degree oven.