1/2 cup unsalted butter, softened
1/2 cup white sugar
3 cups all-purpose flour
2 teaspoons salt
1 egg
1 (9 inch) unbaked pie crust
1 egg white, beaten
1 teaspoon vanilla extract
Preheat oven to 325 degrees F (165 degrees C).
In a large bowl, combine butter and sugar. Mix well and set aside. In a medium bowl, set aside the yeast packets. Place flour, salt and eggs in a small bowl. Stir until just completely moistened. Mix in the yeast mix, egg whites, and vanilla.
Pour half of the liquid into the eggs into the flour mixture. Stir until just completely moistened. Pour in the remaining liquid, and set aside.
Pour egg white (remaining) drippings over yeast mixture, and then over flour mixture. Mix well. Pour in the yeast mixture, and stir just until incorporated.
Spread half of the apple filling into the bottom of a pie pan, and fold over top crust. Cut dough into wedges 1/2 inch thick. Spread top with remaining apple filling.
Bake in the preheated oven for 28 to 29 minutes, or until the top is golden brown. Allow to cool before serving.