Preheat the oven to 350 degrees. Spray a deep dish 10-inch pie plate with nonstick cooking spray.
Cook the pasta per the package instructions just until its al dente.
As the pasta cooks, start the sauce by heating a 12-inch nonstick skillet with the olive oil over medium-high heat until oil shimmers. Add onion and cook for 3-5 minutes or until the onions are soft. Add the beef to the onions and continue to cook until the beef is cooked through and there is no longer any pink. Drain off any excess fat from the skillet. Add tomato sauce, tomato paste, sugar, basil, oregano, salt, and pepper, to the skillet and simmer for about 10 minutes.
When pasta is cooked to al dente, drain well in a colander but Do Not Rinse. Return drained pasta to the pot and add garlic, butter, Parmesan, egg, basil, 1 Teaspoon oregano and pepper and mix to combine. Press pasta mixture with a spatula into prepared pie plate. Bake in preheated oven for about 15-20 minutes or until pasta is set. Allow cooling while you mix together the ricotta mixture.
As the pasta crust cools and the meat sauce simmers, stir the ricotta, egg, 1/2 Teaspoon oregano and pinch of nutmeg together in a small bowl. Spread the ricotta mixture over the slightly cooled pasta crust then pours an even layer of the meat sauce on top. Sprinkle top with cheese and bake. Bake in the oven until heat through and the top is golden and sauce is bubbly about 25-30 minutes. Remove from oven and let sit for about 15 minutes then cut and serve.