Begin by preheating your oven to 375°F (190°C) to ensure an even bake.
In a generous pot, bring salted water to a rolling boil. Once boiling, add the lasagna noodles and cook according to package instructions until they are al dente. Drain the noodles and lay them flat on parchment paper or a clean kitchen towel to cool and prevent sticking.
In a large skillet, heat a splash of olive oil over medium heat. Add the finely chopped onion and minced garlic; sauté for about 3-4 minutes until the onion is softened and fragrant.
Incorporate the ground beef and Italian sausage into the skillet. Cook, breaking the meat into small crumbles as it browns, for approximately 8-10 minutes. Once browned, drain the excess fat from the skillet.
Stir in the crushed tomatoes, tomato sauce, chopped basil, oregano, and season with salt and pepper. Allow the sauce to simmer on low heat for 15-20 minutes, stirring occasionally to enhance the flavors.
In a mixing bowl, combine the ricotta cheese, egg, a pinch of salt, and half of the grated Parmesan cheese. Mix thoroughly until well incorporated and creamy.
In a 9x13 inch baking dish, first spread a thin layer of the meat sauce on the bottom. Place 4 noodles across the sauce. Over the noodles, spread half of the ricotta mixture, followed by one-third of the mozzarella cheese. Layer on more meat sauce, then repeat the process: noodles, remaining ricotta, mozzarella, and meat sauce, until all ingredients are used. Finish with a final layer of noodles, topped with the remaining meat sauce, mozzarella, and the rest of the Parmesan cheese.
Cover the baking dish tightly with foil (to prevent sticking, spray the foil with cooking spray or line it with parchment paper on the cheese side). Bake in the preheated oven for 25 minutes. After that, remove the foil and bake for an additional 25 minutes, or until the cheese is melted, bubbly, and golden brown.
Once baked, allow the lasagna to rest for about 15 minutes before slicing to help it set. Finish by garnishing with freshly chopped parsley for a pop of color.
Notes
Let the lasagna rest before slicing for best results.