Preparation: Preheat your oven to 375°F (190°C).
Boil the Noodles: Cook the lasagna noodles according to the package instructions in a large pot of salted boiling water. Once cooked, drain the noodles and set them aside.
Cook the Meat and Onions: In a skillet or sauté pan over medium heat, cook the ground beef or Italian sausage until it's browned and cooked through. Add the finely chopped onions and minced garlic, and sauté until the onions are soft and translucent. Drain any excess fat from the meat mixture.
Prepare the Cheese Mixture: In a mixing bowl, combine the ricotta cheese, 1 cup of shredded mozzarella, grated Parmesan, beaten egg, chopped basil, chopped oregano, salt, and pepper. Mix well until everything is thoroughly combined.
Layer the Lasagna: In a 9x13-inch (23x33cm) baking dish, spread a thin layer of marinara sauce at the bottom. Place a layer of cooked lasagna noodles over the sauce. Add half of the meat mixture, followed by a layer of the cheese mixture. Repeat the layers with the remaining ingredients, finishing with a layer of marinara sauce on top.
Bake the Lasagna: Cover the baking dish with aluminum foil and bake in the preheated oven for about 30 minutes. Then, remove the foil and continue baking for an additional 15 minutes or until the cheese on top is golden and bubbly.
Serve and Enjoy: Remove the Lasagna from the oven and let it cool slightly before slicing and serving. Garnish with additional fresh basil and oregano if desired.