1 1/2 c. sugar
1/2 c. (1 stick) butter, melted and cool
3 eggs, beaten to blend
2 tbsp. all-purpose flour
2 tbsp. cider vinegar
1 tbsp. vanilla
1 (9 inch) unbaked pie shell

Preheat oven to 300 degrees. In large bowl beat first six ingredients with electric mixer on high speed. Beat about one minute or until smooth. Pour into pie shell. Bake in oven about 50 minutes until top forms pale golden crust (inside will be slightly liquid). Cool completely. Serve at room temperature.