Preheat the Oven: Preheat your oven to 375°F (190°C).
Cook the Beef Mixture: In a large skillet, heat the olive oil over medium heat. Add the chopped onion and cook until softened, about 5 minutes. Add the minced garlic and cook for another minute, until fragrant. Add the ground beef to the skillet. Cook until browned, breaking it up with a spoon as it cooks. Drain any excess fat from the skillet.
Prepare the Sauce: Add the spaghetti sauce to the cooked beef mixture. Stir in the Italian seasoning, salt, and pepper. Let the sauce simmer on low heat for about 5 minutes.
Assemble the Lasagna: In a 9x13 inch baking dish, spread a thin layer of the meat sauce on the bottom. Arrange a single layer of thawed cheese ravioli over the sauce. Evenly sprinkle on half of the mozzarella and parmesan cheese. Spread half of the remaining meat sauce over the ravioli. Add another layer of cheese ravioli. Spread the remaining meat sauce over the ravioli. Sprinkle the remaining 1 cup of mozzarella cheese over the top. Finally, sprinkle the Parmesan cheese evenly over the mozzarella.
Bake: Cover the baking dish with aluminum foil and bake in the preheated oven for 30 minutes. After 30 minutes, remove the foil and bake for an additional 10-15 minutes, or until the cheese is melted and bubbly.
Serve: Remove the lasagna from the oven and let it sit for about 10 minutes before serving.