Here’s a recipe that is over 100 years old (with updated preparation). This was a cherished family favorite.
1 unbaked 9-inch pie shell
1/2 cup butter, softened
2 cups sugar
4 eggs, separated
2 Tbsp. apple cider vinegar
In medium mixing bowl, cream together butter and sugar. Add egg yolks, one at a time, mixing well to incorporate. Add vinegar and mix well.
In separate bowl, beat egg whites until holds peak and is stiff. Gently fold egg whites into butter mixture. Pour into 9-inch unbaked pie shell. Bake in preheated 375 degree oven for 10-15 minutes or until set. Remove from oven and place on cooling rack. Cool completely before serving.
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