Cook the pasta according to package directions until it is al dente. Drain and set aside.
In a large skillet, brown the ground beef over medium-high heat. Add the onion and garlic, and cook untilthe onion is translucent and the beef is fully cooked
Add the crushed tomatoes, tomato paste, oregano, cinnamon, salt, and pepper to the skillet. Stir everythingtogether and let it simmer for 15-20 minutes.
While the sauce is simmering, prepare the bechamel sauce. Melt the butter in a medium saucepan overmedium heat. Add the flour and whisk until it forms a smooth paste. Gradually add the milk, whiskingconstantly to prevent lumps from forming. Add the nutmeg and continue to whisk until the sauce thickens,about 10 minutes
Remove the bechamel sauce from the heat and add the beaten eggs and half of the grated parmesan cheese.Stir until everything is well combined.
In a large baking dish, layer half of the cooked pasta on the bottom. Add a layer of the meat sauce on top ofthe pasta. Add another layer of pasta on top of the meat sauce, followed by another layer of meat sauce. Addthe remaining pasta on top of the meat sauce, then pour the bechamel sauce over the top, spreading itevenly with a spatula. Sprinkle the remaining parmesan cheese on top of the bechamel sauce.
Bake the pastitsio for 45-50 minutes, or until the top is golden brown and the edges are bubbling. Allow it tocool for 10-15 minutes before serving. Enjoy!