Preheat the oven:
Preheat your oven to 375°F (190°C). Grease a 9x13-inch baking dish.
Cook the meat:
In a large skillet, cook the ground beef or Italian sausage over medium heat until browned, breaking it up as it cooks (about 6-8 minutes). Drain any excess fat.
Add the jar of marinara or pasta sauce to the cooked meat, stir, and simmer for a few minutes to combine. Season with salt and pepper to taste.
Prepare the creamy cheese mixture:
In a medium mixing bowl, combine the softened cream cheese, ricotta cheese, sour cream, garlic powder, Italian seasoning, and 1 cup of the shredded mozzarella. Stir until smooth and creamy.
Assemble the casserole:
Spread 1/3 of the meat sauce mixture in the bottom of the prepared baking dish.
Arrange half of the ravioli over the sauce in a single layer.
Spread half of the creamy cheese mixture over the ravioli.
Add another 1/3 of the meat sauce on top.
Repeat the layers with the remaining ravioli, creamy cheese mixture, and the rest of the meat sauce.
Top with cheese:
Sprinkle the remaining 1 cup of shredded mozzarella and the grated Parmesan cheese over the top of the casserole.
Bake the casserole:
Cover the dish with aluminum foil and bake in the preheated oven for 30 minutes.
Remove the foil and bake for an additional 10 minutes, or until the cheese on top is golden and bubbly.
Serve:
Let the casserole cool for 5-10 minutes before serving. Garnish with fresh basil or parsley, if desired.