Cook the pasta sheets in boiling, salted water until al dente. Shock the pasta in cold water. Lay the pasta out onto a clean kitchen towel and dry.
Take 1/2 of the melted butter and coat the bottom a 13 by 9 by 2-inch pan. Place a layer of pasta to cover bottom of pan. Ladle a thin layer of tomato sauce over the pasta, and sprinkle with 1/4 of the mozzarella. Add another layer of pasta sheets over the cheese. Ladle a thin layer of bechamel sauce over the pasta. Sprinkle 1/4 of the ground veal and 1/4 of the Parmigiano evenly over the bechamel. Repeat layering, until there are 3 layers of each. Add the final layer of fresh pasta and cover top layer with the remaining mozzarella, veal, Parmigiano and tomato sauce. Finally, ladle the remaining 1/4 cup of melted butter over the top and cover the pan with aluminum foil.
Bake approximately 30 minutes. Let stand for about 10 minutes before serving.
Saute the onion in olive oil until brown. Add the tomatoes and bring to a simmer. Crush tomatoes with a fork as they soften. Season with salt and pepper and add basil. Simmer for about 1 hour.
Bring the milk to a simmer in a saucepot. In a saute pan, combine the melted butter with the flour to make roux. Whisk the milk into the roux. Bring to a simmer and cook for 2 minutes. Remove from the heat and set aside.
Melt the butter in a saute pan. Add the veal and cook until brown and cooked through. Season with salt, pepper, and nutmeg. Drain off excess liquid and set aside.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.