Heat a large, deep skillet over medium heat. Add the ground beef and break it up as it cooks.
When meat is mostly cooked through stir in the onion and 2 cloves of garlic. Continue cooking until meat is cooked through. Drain fat and return to pan.
Add the marinara, water, and cheese ravioli to the skillet. Stir to submerge the ravioli in the pasta sauce.
Bring to a boil, cover, and simmer for 8 minutes or until the pasta is tender.
Stir together the ricotta cheese, Parmesan, 1/4 cup mozzarella, remaining clove of minced garlic, and parsley.
Remove the skillet from the heat and drop spoonfuls of the ricotta mixture over the pasta. Spread to cover the pasta. Sprinkle with remaining 1/2 cup of mozzarella.
Cover the skillet and let sit for 5 minutes to melt the mozzarella. Sprinkle with additional parsley before serving, if desired.