In a bowl mix together the ground meat with the scallions, parsley, breadcrumbs, olive oil and eggs. Season with red pepper and salt. Work the mixture well with the hands, cover and refrigerate for 30 minutes, and up to 4 hours.
In a bowl mix the oil with the yogurt and eggs –reserving 3 tablespoons of the eggs— the cheese and plenty of pepper. Taste and add salt if needed –usually feta is quite salty.
In a large skillet warm 3-4 tablespoons olive oil and sauté the leeks over medium heat, stirring every now and then, until soft, about 15 minutes. Preheat the oven to 400.
The French would call this a flan, I suppose, but this rustic Balkan dish—called mamaliga in some parts of mainland Greece—uses cornmeal as thickener with just two eggs and no cream.