Filling:

1. Add the onion (1) and garlic cloves (4) to the bowl. Chop Speed 7 / 3 seconds. Scrape down sides.
2. Add the butter (40g) to the bowl. Program 5 minutes / 100C / Speed 2.
3. Add the feta cheese (500g), parsley (1/2 bunch), salt (1 tsp) and pepper (1 tsp) to the bowl. Mix Speed 5 / 6 seconds.

Assembly:

1. Preheat the oven to 180C. Line a large baking tray with baking paper.
2. Place the egg (1), butter (20g) and milk (2 Tbsp) into a small bowl. Whisk to combine.
3. Lay one sheet of filo pastry (10 total) onto the prepared tray so that the sides of the sheets are hanging over the edge of the tray.
4. Brush the sheet of pastry with the egg mixture. Tear any of the overhanging parts and place them on top of the brushed sheet of pastry.
5. Place another sheet of pastry on top and repeat the process until you have used 5 sheets of filo.
6. Spoon the cheese mixture onto the pastry and spread it out evenly so that all the pastry is covered.
7. Lay another sheet of pastry over the cheese mixture so that the sides of the sheets are hanging over the sides of the tray.
8. Brush the sheet of pastry with the egg mixture. Tear any of the overhanging parts and place them on top of the brushed sheet of pastry.
9. Place another sheet of pastry on top and repeat the process until you have used 5 sheets of filo.
10. Use the last of the egg mixture to brush the top of the pastry. Sprinkle with black cumin seeds (2 Tbsp).
11. Bake for 35-40 minutes or until golden.
12. Cover with a tea towel and allow to cool before cutting into squares. Serve warm or cold.