Vinegar Pie

4 Eggs
1-1/2 Cups Sugar
1/4 Cup Butter or margarine, melted
1-1/2 Tbsp. Cider or white distilled vinegar
1 Tsp. Vanilla extract
9-inch Frozen pie shell, defrosted

Preheat over to 350ºF. In a large mixing bowl, combine eggs, sugar, butter, vinegar and vanilla; mix well. Pour into pie shell. Bake until firm, about 50 minutes. Cool on a rack. Serve garnished with nuts or whipped cream, if desired.