1. Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish.
2. In a skillet, cook the ground beef and onion over medium heat until browned. Drain excess grease, then stir in marinara sauce, garlic powder, Italian seasoning, salt, and pepper. Simmer for 5 minutes.
3. In a bowl, mix ricotta cheese, egg, and 1/4 cup Parmesan until smooth.
4. Spread a thin layer of meat sauce in the bottom of the baking dish. Layer 3 lasagna noodles, followed by more meat sauce, a dollop of the ricotta mixture, and a sprinkle of mozzarella. Repeat layers twice, ending with mozzarella and remaining Parmesan on top.
5. Cover with foil and bake for 25 minutes. Remove the foil and bake for another 15 minutes until bubbly and golden.
6. Let rest for 10 minutes before slicing. Garnish with fresh parsley.