1. Bring a large pot of salted water to a boil and cook the lasagna noodles until al dente. Drain and lay flat to prevent sticking.

2. In a large skillet, cook the ground beef and onion over medium heat until browned. Add garlic and cook for 1 minute.

3. Stir in tomato sauce, tomato paste, and diced tomatoes. Season with Italian seasoning, sugar, salt, and pepper. Simmer for 20–25 minutes.

4. In a bowl, mix ricotta cheese with egg, half the parsley, salt, and pepper.

5. Preheat oven to 375°F (190°C). Spread a thin layer of meat sauce in a 9×13-inch baking dish.

6. Layer noodles, ricotta mixture, mozzarella, and meat sauce. Repeat layers, finishing with sauce and topping with mozzarella and Parmesan.

7. Cover with foil and bake for 25 minutes. Remove foil and bake an additional 20 minutes until bubbly and golden.

8. Let rest for 15 minutes before slicing. Garnish with remaining parsley.