Step 1: Preheat your oven to 180°C (350°F) and lightly grease a 9x13 inch (23x33 cm) baking dish.
Step 2: In a large bowl, combine the cottage cheese, 2 eggs, crème fraîche, and salt. Mix well until everything is thoroughly combined and creamy.
Step 3: Carefully unroll the thawed filo pastry. Cover the sheets with a damp cloth to prevent them from drying out while you work.
Step 4: Place one sheet of filo pastry in the prepared baking dish, letting the excess hang over the sides. Brush lightly with melted butter.
Step 5: Repeat with 5-6 more filo sheets, layering them and brushing each with melted butter. Ensure the hanging edges are evenly distributed around the dish.
Step 6: Spread the entire cheese mixture evenly over the buttered filo layers.
Step 7: Fold the overhanging filo edges over the filling. Then, layer the remaining filo sheets on top, brushing each one generously with melted butter. Tuck in any loose edges to create a neat top.
Step 8: Score the top layers of the pie with a sharp knife into serving portions (squares or diamonds). Do not cut all the way through to the filling.
Step 9: Whisk the remaining egg with a tablespoon of water to create an egg wash. Gently brush the top of the pie with this egg wash for a beautiful golden finish.
Step 10: Bake for 40 minutes, or until the Tiropita is golden brown and puffed up. If it's browning too quickly, you can loosely tent it with foil.
Step 11: Remove from the oven and let it cool for at least 10-15 minutes before slicing and serving. This allows the pie to set and makes it easier to cut.