I made this for a friend while she was recouperating from surgery. It's very warm and satisfying. The eggplant kind of melts into the meat sauce giving it a rich flavor, and the pecorino in the cheese sauce gives it just the right zing. —Berna
To make beef and eggplant ragout: In a large heavy saute pan, cook the onions until they begin to soften. Add the ground beef and saute over medium heat, breaking up clumps, until no longer pink, about 5 minutes longer. Add the garlic, salt, cinnamon and pepper and stir to combine. Make some room at the bottom of the pan, add the tomato paste and cook for a minute to caramelize. Then add the eggplant and tomatoes, bring to a simmer, cover and cook for about 15 minutes, stirring occasionally, until the eggplant literally "melts" into the meat sauce.
To make the Cheese Sauce: Melt butter in a heavy 2 quart saucepan then stir in flour and cook over moderate heat, stirring for about 2 minutes. Whisk in the milk and slowly bring to a boil, whisking constantly until thickened. Add the cheese, salt and pepper and mix until all the cheese has been incorporated into the sauce. Let the sauce cool a bit before adding the eggs. Beat the eggs in a large bowl and gradually add the cheese sauce , stirring to combine.
Cook the pasta in a large pot of boiling, salted water until al dente, and then drain in a colander.
To assemble: Toss half the pasta with the beef and eggplant ragout and half with the cheese sauce. Pour the pasta with the beef ragout into a 3 quart baking dish, spreading evenly. Pour the pasta with cheese sauce on top, spreading evenly.
Bake at 375 degrees, uncovered, for 35-45 minutes, until bubbly and golden. Let rest for 5 minutes before serving.