Preheat your oven to 400° F and grease a 9x13 baking dish.
Spread about 3/4 cup of pasta sauce onto the bottom of the baking dish.
Arrange half of the frozen ravioli in a single layer over the sauce, followed by half of the remaining sauce and half of the shredded mozzarella cheese.
Repeat the layering process with the remaining ravioli, then top with leftover sauce and cheese. Sprinkle parmesan on top if desired.
Cover the baking dish with aluminum foil and bake for about 30 minutes. Remove the foil and bake for an additional 15 minutes until the cheese is bubbly and golden brown.
Let it cool slightly before serving alongside veggies, salad, or garlic bread.