Cook pasta according to package instruction.
In a large bowl, place ricotta, egg, parmesan cheese, ½ C mozzarella, salt, pepper and parsley. Stir to combine. Set aside.
Preheat oven to 350.
Drain pasta and return to pot (not over heat). Stir in 1 jar of the sauce. Stir the ricotta mixture into the pasta.
Spread half of the pasta mixture on the bottom of a 9x13 (or similar) baking dish. Place meatball slices over pasta and then sprinkle ½ C cheese over meatballs. Add remaining pasta mixture. Pour second jar of sauce over the top of everything.
Cover bake at 350 for 25 minutes.
After 25 minutes, remove cover and sprinkle remaining cheese over the top. Return to oven, uncovered, for another 10 minutes.
If desired, garnish with additional chopped parsley.
Mangia!