In a large Dutch oven, heat 2 tablespoons of olive oil over medium heat. Add ground beef and Italian sausage, browning for 5–7 minutes until cooked. Stir in chopped onion and minced garlic, sautéing for an additional 3–4 minutes. Incorporate San Marzano tomatoes, crushed tomatoes, tomato paste, sugar, salt, pepper, and Italian seasoning. Let simmer for 30 minutes.

In a mixing bowl, combine ricotta, beaten egg, Parmesan, and chopped parsley. Mix until creamy, adjusting texture with milk if necessary.

If using traditional noodles, boil salted water and cook noodles according to package directions until just shy of al dente. Drain thoroughly and lay flat. Skip this step if using oven-ready noodles.

Preheat oven to 375°F (190°C). In a greased baking dish, layer meat sauce, noodles, half of the ricotta mixture, and sprinkle mozzarella. Repeat layers and finish with meat sauce and mozzarella.

Cover lasagna with aluminum foil and bake for 30 minutes. Remove foil and bake for an additional 15 minutes until cheese is bubbly and golden.

Let the lasagna rest for 20–25 minutes before serving, allowing layers to set.