In a large skillet over medium heat, brown the sausage and ground beef with minced onion and crushed garlic for about 5-7 minutes until meat is no longer pink. Stir in crushed tomatoes, tomato sauce, tomato paste, and water. Add white sugar, chopped parsley, dried basil, salt, Italian seasoning, fennel seeds, and black pepper. Let simmer for 30 minutes, stirring occasionally, until thickened.

While the sauce simmers, preheat your oven to 375°F (190°C). This step is essential for ensuring even baking.

In a mixing bowl, combine ricotta cheese with a beaten egg and half of the remaining chopped parsley. Season with a pinch of salt. Stir until smooth and creamy.

In a 9x13 inch baking dish, layer the lasagna, starting with a thin layer of meat sauce, then lasagna noodles, cheese mixture, and mozzarella slices. Repeat layers until all ingredients are used, finishing with a layer of sauce and remaining mozzarella and Parmesan.

Cover the lasagna with aluminum foil, ensuring it doesn’t touch the cheese. Bake for 25 minutes. Then remove foil and bake for an additional 25 minutes until bubbly and golden.

Let the lasagna rest for about 15 minutes before slicing. This resting time allows the layers to set.