Bolognese Sauce: Heat oil over medium heat in a large pot. Add onions, carrots, celery and garlic. Saute for about 10 minutes until vegetables begin to brown. Increase the heat to high and add the pancetta. Saute for 3 minutes. Add the meatloaf mix and the ground pork and continue to cook until meat is no longer pink, breaking up meat with a fork. Add the milk and cook, stirring often until most of the milk is cooked down, about 15 minutes. Add the tomatoes, chicken stock and white wine. Reduce heat to medium low and simmer for 1 hour, uncovered, stirring occasionally. Add the tomato paste and mix until incorporated. Continue to cook for 20 more minutes. Season with the salt and pepper. Remove from heat and set aside.

Bechamel Sauce: Add the milk to a medium saucepan and bring to a simmer over medium heat. In another saucepan, melt butter over medium heat. Whisk in flour. Reduce the heat to low and cook for 1 minute, whisking often. Slowly whisk in the milk a ladle at a time. Increase the heat to medium low and simmer, whisking often until the sauce is smooth and thickened, about 5 minutes. Add salt, pepper and nutmeg.

Preheat oven to 375 degrees. Spray a large deep 13x9 baking dish with nonstick cooking spray.

Assembling the lasagna: Spread about 3/4 cup bolognese in bottom of dish. Top with lasagna sheets overlapping slightly. I used O'Sole Mio fresh lasagna sheets from my grocery's refrigerated section. The sheets are about 5x9 inches. For each layer of pasta I used three sheets. Two full sheets, and then I cut another sheet into two pieces to cover the additional space. Sprinkle 1/4 cup of the parmesan and 3/4 cup of the shredded mozzarella. Top with about 2 cups of the bolognese, spreading with a rubber spatula, then 1 cup of the bechamel, also spreading with the rubber spatula to the edges.Repeat pasta, parm, mozzarella, bolognese, bechamel two more times. Finish with a layer of pasta, the remaining bechamel, and then the remaining bolognese. I like to place a few scoops of the bolognese randomly on top of the bechamel and then just slightly spread. Then sprinkle remaining shredded mozzarella, also in random clumps here and there on top, then a sprinkle of the remaining parm. Dot the top of the lasagna with the small cubes of butter.

Cover with foil and place baking dish on a large baking sheet. Bake for 30 minutes covered, then remove the foil and continue to bake for 15 minutes uncovered until lightly browned and until the sauce is bubbly. Let stand for 10 minutes, then sprinkle with parsley, if desired. Cut into squares and serve immediately.