In a large bowl, sift the flour and add the cold cubed butter. Using your hands or a pastry cutter, work the flour and butter together until the mixture resembles coarse sand.

Add the whole egg, egg yolk, sugar, and salt. Mix until a homogeneous dough forms. Avoid overworking the dough to maintain its flaky texture.

Wrap the dough in plastic wrap and refrigerate for at least 30 minutes.

Preheat the oven to 180°C (350°F).

Remove the dough from the refrigerator and roll it out on a floured surface. Line a pie dish with the rolled dough, ensuring even coverage of the bottom and sides. Trim excess dough.

Peel and thinly slice the apples.

Spread a layer of applesauce on the pie crust base. Arrange the apple slices over the applesauce and sprinkle with sugar to taste.

Bake in the preheated oven for approximately 40-45 minutes, or until the crust is golden brown and the apples are tender.

Remove from the oven and allow to cool before removing from the pan.