Begin by boiling a large pot of salted water. Once boiling, add the lasagna noodles, cooking according to package instructions until al dente, about 8-10 minutes. Drain and set aside.

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

In a medium bowl, combine ricotta cheese, egg, and 1/4 cup of grated Parmesan cheese. Mix until smooth and creamy.

Preheat your oven to 375°F (190°C). In a deep baking dish, layer meat sauce, noodles, half of the ricotta mixture, a third of the mozzarella. Repeat layers, finishing with noodles and remaining meat sauce and mozzarella.

Cover with aluminum foil and bake for 25 minutes. Remove foil and bake uncovered for an additional 20 minutes until cheese is bubbly and golden brown.

Let the lasagna cool for 10 minutes before serving. Garnish with fresh basil or parsley if desired.