Cook Noodles: Start by bringing a large pot of salted water to a boil. Once boiling, add the lasagna noodles and cook according to the package instructions, usually around 8-10 minutes. Drain and set aside.

Prepare Meat Sauce: In a large skillet, heat olive oil over medium heat. Add ground beef and sauté until browned, about 5-7 minutes. Drain fat, stir in marinara sauce, diced tomatoes, and Italian seasoning. Simmer for 10 minutes, seasoning with salt and pepper.

Prepare Ricotta Mixture: In a bowl, combine ricotta cheese, beaten egg, and grated Parmesan cheese. Mix until smooth and creamy.

Assemble Lasagna: Preheat oven to 375°F. Spread a small amount of meat sauce in a baking dish to prevent sticking. Layer noodles, half of the ricotta mixture, mozzarella, and meat sauce; repeat, finishing with noodles, remaining meat sauce, and mozzarella.

Bake: Cover with foil and bake for 25 minutes, then remove foil and bake an additional 20 minutes until cheese is bubbly and golden brown.

Let it Rest: Remove from oven and let cool for 10 minutes before slicing. Garnish with fresh basil or parsley.