In a small bowl, add ¾ cup warm milk (100°F-110°F), 1 packet (7g) active dry yeast, 2 tablespoons granulated sugar and mix it. Add there 1 tablespoon of flour (from the whole amount) and whisk it briefly. Set aside to activate the yeast.
In a large mixing bowl, whisk 1 egg and 3 tablespoons butter, softened until just combined. Pour the yeast and milk mixture to the bowl with egg and butter. Whisk briefly.
Gradually start mixing in 2¾ cups (350g)* all purpose flour until the sticky dough forms. Transfer the dough onto the floured surface and knead it for about 5 minutes until no longer sticky. Add more flour if needed.
Form the bowl and brush it lightly with olive oil. Place it in a clean bowl, cover and let it rise in a warm place for 1 hour or until it doubles in size.
Preheat oven to 350°F. Line 9-inch deep pie dish with parchment paper or grease it with oil/butter.
Uncover the dough, punch it down and divide it into 2 parts. Roll out the larger part into the circle and place in in a prepared pie pan, ensuring the edges cover the rims of the pan.
Add about 2-3 cups braised cabbage filling (the more the better) on top, spreading it evenly and pressing gently. Roll out the second portion of dough into the circle and place it over the pie, pinching the edges to seal. Pierce at least one hole in the center to allow the steam to escape.
Brush the top of the pie with the egg wash. Let it rest for 10 minutes.
Bake cabbage pie at 350°F for 35-40 minutes or until it is golden brown. Remove from the oven and let cool down for 10 minutes before slicing it.