In a large skillet over medium heat, brown the Italian sausage and ground beef along with the chopped onion and minced garlic. Cook until the meats are no longer pink, about 8-10 minutes. Stir in the crushed tomatoes, tomato paste, and tomato sauce. Add the water, sugar if desired, and season with basil, fennel seeds, Italian seasoning, salt, and pepper. Allow the sauce to simmer, covered, for 1½ hours, stirring occasionally.

While the sauce is simmering, prepare the cheese mixture. In a medium bowl, combine the ricotta cheese with a beaten egg and finely chopped parsley. Mix thoroughly until smooth and well incorporated. Set this aside.

Preheat your oven to 375°F (190°C). In a greased 9x13-inch baking dish, spread a layer of the sauce mixture on the bottom. Place the oven-ready lasagna noodles over the sauce, then add half of your ricotta mixture and sprinkle with mozzarella cheese. Repeat the layers, finishing with a final layer of noodles, a generous amount of sauce, and top with remaining mozzarella and grated Parmesan cheese.

Cover the assembled lasagna with foil, ensuring the foil is sprayed with non-stick cooking spray. Place in the preheated oven and bake for 25 minutes. Remove the foil and bake for an additional 25 minutes, or until the cheese is melted and bubbly with a golden top.

Once baked, remove the lasagna from the oven and let it rest uncovered for 15 minutes before serving.