Cook pasta according to package directions; drain. Toss with butter and 1/2 cup grated Parmesan cheese. Transfer to a greased 9 x 13-inch baking dish.

In a large skillet, cook beef and onion over medium heat until beef is no longer pink, breaking beef into crumbles. Drain fat; add garlic and cook 2 minutes longer. Stir in tomato sauce, salt and cinnamon; heat through. Spoon over pasta and sprinkle with remaining 1/2 cup Parmesan cheese.

Bechamel Sauce: In a large sauce pan, melt butter. Whisk in flour, salt and pepper until smooth. Gradually add milk and bring to a boil. Cook and stir constantly until thickened (about 2 minutes or so).

In a small bowl, whisk eggs first then add a small amount of hot mixture into eggs and whisk to blend. Return to pan, whisking constantly. Bring to a gentle boil; cook and stir 2 minutes until saucy.

Pour sauce over beef mixture. Sprinkle with 1 cup shredded Parmesan cheese.

Bake at 350 degrees, covered (use foil) for 20 minutes. Uncover and bake 30-40 minutes longer or until top is golden brown all over.

Remove from oven and let stand 5 minutes before serving.