In a large mixing bowl, combine the all-purpose flour, salt, instant yeast, lukewarm water, sugar, olive oil, and plain yogurt.
Use a stand mixer with a hook attachment or mix by hand until you form a soft, elastic dough. It should be slightly sticky but manageable. Add more flour if needed.
Transfer the dough to a greased bowl, cover it, and let it rise in a warm place for an hour until it doubles in size.
**Making the Cheese Filling:**
While the dough is resting, prepare the cheese filling. In a bowl, mix together the mozzarella cheese, feta cheese, parsley, beaten egg, onion powder, dried mint, Aleppo pepper, black pepper, garlic powder, and nigella seeds. Set aside.
**Assembly:**
Preheat your oven to 475°F.
After the dough has risen, punch it down and divide it into 12 equal portions, shaping each into a tight ball.
Roll out each piece into an oval/football shape.
Add a generous amount of cheese filling to the center of each oval, then fold over the left and right sides, pinching the top and bottom to create a boat-like shape.
Place the filled dough on a baking sheet lined with parchment paper. Brush the edges with milk or heavy cream.
Bake for 10 to 12 minutes until the edges turn golden brown.
Let them cool for a few minutes before enjoying them warm.