In a skillet, saute ground meat in olive oil with onions until browned. Season with salt, oregano and pepper. Add tomato sauce and cinnamon. In a small bowl, beat eggs and stir in cheese. When ground meat has cooled, fold in the eggs and cheese mixture.
Butter a 9x13 inch baking pan. Arrange six sheets of phyllo pastry on bottom of pan, buttering each sheet. Spread a layer of cooled meat mixture evenly on phyllo. Cover with remaining six sheets, brushing each with melted butter. Trim edges of phyllo to fit pan with a sharp knife. Slice through top of pastry to form diamond shapes.
Bake in a preheated 350°F oven until pastry is golden crisp.