Prepare the Spaghetti Crust: Cook the spaghetti according to the package instructions, then drain and set aside to cool slightly. In a large bowl, combine the cooked spaghetti, eggs, Parmesan cheese, mozzarella cheese, olive oil, salt, and pepper. Toss to coat the pasta evenly. Grease a 9-inch pie dish and press the spaghetti mixture into the bottom and up the sides to form a ‘crust’. Bake in a preheated 375°F (190°C) oven for 10-12 minutes until the crust is golden. Remove from the oven and set aside.

1. Prepare the Filling: If using meat, cook the ground beef or sausage in a skillet over medium heat until browned. Drain any excess fat and stir in the marinara sauce. Season with salt, pepper, garlic powder, onion powder, and basil, then simmer for 5 minutes.
2. Prepare the Cheese Filling: In a bowl, combine the ricotta, shredded mozzarella, and Parmesan cheeses. Mix until smooth.
3. Assemble the Spaghetti Pie: Spread the ricotta cheese mixture evenly over the baked spaghetti crust. Pour the marinara sauce (with or without meat) over the ricotta layer, spreading it evenly. Return the pie to the oven and bake for 20-25 minutes until the top is golden and bubbly.
4. Serve: Let the pie cool for 5-10 minutes before slicing and serving.