Start by mixing the flour, yogurt, olive oil and salt in a bowl.
Once a dough is formed, cover with film and set aside for 30 minutes.
In the meantime, prepare the white beets. Wash them and cut them into medium-sized pieces.
Add salt and massage the curls. Put them in a strainer for 10-20 minutes until they release juices.
Drain them well and mix them with the grated feta, the 2 tbsp. olive oil, salt and pepper.
Divide the dough in half. You want one piece to be bigger than the other because it will be the bottom sheet.
Open the bottom sheet. Transfer it to a greased pan. Put the curls on top and spread the second leaf on top. Bring the bottom sheet over the top sheet and seal the filling inside the two sheets.
Oil the top sheet.
Bake in a preheated oven at 180C for 50-60'.
Remove the pie from the oven and let it cool for 15 minutes before cutting.