Cream butter and sugar together in a large bowl. Add flour, cinnamon, allspice, salt, egg, vinegar and water. Mix well. Pour mixture into the top of part of a double boiler and cook over hot water until filling is smooth and thick, stirring constantly so it won't burn. Pour filling into the baked pie crust. Serves 6 to 8.

Pie may be eaten as is or topped with meringue and browned lightly in the oven. If making a 9 inch pie, double the recipe.