Preheat your oven to 375°F and spray a 9x13-inch baking dish with cooking spray.
Spread 1 cup of marinara sauce on the bottom of the prepared baking dish.
In a medium bowl, mix together ricotta cheese, 1 cup mozzarella, Parmesan, Italian seasoning, and garlic powder.
Layer half of the frozen ravioli over the sauce, then dollop half of the cheese mixture on top and spread gently.
Pour half of the remaining marinara sauce over the cheese layer, then repeat with remaining ravioli, cheese mixture, and sauce.
Cover tightly with foil and bake for 30 minutes.
Remove foil, sprinkle remaining 1 cup mozzarella on top, and bake uncovered for 5 more minutes until cheese is melted and bubbly.
Let stand 5 minutes before serving. Garnish with fresh basil if desired.