Flling: In a large bowl, beat the eggs with the yoghurt. Add the cheeses, salt and pepper and mix all the ingredients well. Preheat the oven to 200 C. Melt the butter (2 tablespoons) and add to a cup of olive oil. Place half the phyllo dough in a buttered baking pan. Pour in the filling and cover with the remaining phyllo sheets (8 sheets down, 7 up) basting each with a mixture of oil and butter. Using a knife or scissors cut the extra dough over the rim and close the pie, joining the edges from inside. Brush the surface with a beaten egg. Add the glass of milk and cover with sesame seeds. Refrigerate for 2-3 hours.