To begin preparing the filling, peel the apples, then cut them into cubes and sprinkle them with cinnamon. Next, in a small saucepan, combine 1/3 cup of water with the apples and cook over low heat until the apples are soft.

Transfer the cooked apples to a blender and puree them. Set the puree aside to cool. While waiting, you can start making the pie dough.

To prepare the dough, melt the butter in a saucepan. Once the butter turns brown, remove it from the heat and let it cool slightly. Then, add oat bran flour, coconut flour, salt, and 3 tablespoons of water to the melted butter. Mix and knead the ingredients to form a dough, then spread the dough into a small mold.

Preheat the oven to 190°C (374°F).

Now, prepare the topping by peeling the skins of 3 red apples and cutting them into thin slices. Toss the apple slices with lemon juice, cinnamon, and nutmeg, then let them sit for 30 minutes.

Pour the cooked apple puree from the blender onto the dough. Arrange the sliced and marinated apples on top. Place the pie in the oven and bake for about 1 hour, checking periodically until the apples are browned. Baking time may vary depending on the oven.

Bon Appétit!