Preheat oven to 350 degrees. Assemble all ingredients, beat egg with ricotta cheese and reserve.
In a large skillet over medium heat, sauté onion in olive oil until tender, about 5 minutes.
Add ground beef, cook until browned. Drain off any fat.
Add dried herbs and seasonings. Stir to combine.
Pour sauce over meat mixture and bring to a simmer.
Nestle ravioli evenly into sauce and gently simmer for 10 minutes
Sprinkle with Parmesan cheese and dollops of ricotta/egg mixture.
Spread shredded mozzarella evenly on top. Then arrange mozzarella slices on top.
Bake for 10 - 15 minutes until cheese is melted and bubbly. Finish under broiler for a lightly browned cheese topping.
Let rest 10 minutes before serving. Garnish with fresh basil leaves and Enjoy.