In 4 qt sauce pan over high heat, cook ground beef, ground pork, and onion until all pan juices evaporate and meat is well browned, stirring frequently.
Add tomatoes with their liquid, tomato paste, water, basil, pepper, and 1¼ tsp salt.
Heat until boiling. Reduce heat to low; cover and simmer 10 minutes, stirring occasionally.
Skim off fat from sauce, keep warm.
In medium bowl, mix mozzarella cheese, ricotta cheese, eggs, parsley; set aside.
Prepare lasagna noodles as label directs; drain.
Meanwhile, in a 2 qt sauce pan over medium heat, melt butter and stir in flour, nutmeg, and 1/4 tsp salt until blended; book 1 minute. Gradually stir in milk. Cook, stirring constantly, until white sauce is thickened and smooth; remove from heat.
Preheat oven o 375°. In 13“ x 9" baking dish, evenly spoon about ¾ c meat sauce. Arrange half of noodles over sauce, overlapping to fit. Spoon half of cheese mixture over noodles; spread with half of white sauce; top with half of remaining meat sauce. Repeat layering with remaining noodles, cheese mixture, and sauces.
Bake lasagna 45 minutes or until heated through. Remove from oven, let stand 10 minutes for easier serving.