Baked 9 inch pie shell
3 egg yolks, beaten
1/4 tsp. salt
1 c. sugar
1 3/4 c. boiling water
1/4 c. cornstarch
1/4 c. cider vinegar
1/4 c. cold water
1 tsp. lemon extract
3 egg whites (meringue)

Place egg yolks in top of double boiler, add sugar and salt. Gradually add boiling water, stirring constantly. Add vinegar and cornstarch dissolved in cold water.

Cook over boiling water until thick and smooth, about 12 minutes. Remove from heat, add lemon extract. Stir until filling is smooth and blended.