To make lasagna, start by boiling the noodles until al dente and set them aside. In a pan, brown ground beef, drain any excess fat, and mix it with marinara sauce, allowing it to simmer for 10 minutes. In a separate bowl, combine ricotta cheese, an egg, grated Parmesan, salt, and pepper. In a baking dish, layer the meat sauce, lasagna noodles, ricotta mixture, and shredded mozzarella cheese, repeating the layers until all ingredients are used, finishing with mozzarella on top. Cover the dish with foil and bake at 375°F (190°C) for 25 minutes, then remove the foil and bake for an additional 10 minutes until the cheese is golden. Let it cool slightly before serving.