Preheat Oven: Preheat your oven to 375°F (190°C).
Cook the Ground Beef: In a large skillet over medium heat, cook diced onion and ground beef until beef is browned and onion is translucent. Drain excess fat.
Add Seasonings: Stir in Italian seasoning, onion powder, garlic powder, salt, and black pepper. Mix well.
Combine with Marinara: Pour in the marinara sauce and simmer for about 5 minutes to meld the flavors.
Cook the Tortellini: In a separate pot, cook tortellini according to package instructions until al dente. Drain and set aside.
Layer the Ingredients: In a large baking dish, spread a layer of the meat sauce. Add half the cooked tortellini, dollops of ricotta, and half of the mozzarella. Repeat with remaining tortellini, ricotta, and meat sauce. Finish with remaining mozzarella on top.
Bake: Cover with foil and bake for 25 minutes. Remove foil and bake an additional 10–15 minutes until cheese is bubbly and golden.
Serve: Allow to cool a few minutes before slicing. Serve warm.
Serving and Storage Tips
