01 -
Heat olive oil in a large skillet over medium heat. Add ground beef and cook, breaking apart with a spoon, until browned, about 5 to 7 minutes.
02 -
Add diced onion and minced garlic to the beef. Cook until onion is translucent and garlic is fragrant, about 3 to 4 minutes. Season with salt and pepper.
03 -
Stir marinara sauce into the meat mixture and let simmer for 5 minutes to meld flavors and thicken slightly. Remove from heat.
04 -
In a medium bowl, combine ricotta, half the mozzarella, half the Parmesan, chopped basil, and oregano. Mix until smooth and creamy.
05 -
Spread a thin layer of meat sauce on the crockpot bottom. Add a single layer of frozen ravioli over the sauce. Dollop and spread ricotta mixture over ravioli, then top with meat sauce. Repeat layering ending with meat sauce.
06 -
Sprinkle the remaining mozzarella and Parmesan cheeses over the final meat sauce layer.
07 -
Cover and cook on low for 4 to 5 hours until ravioli is tender and cheese is melted and bubbly.
08 -
Turn off the cooker and let stand for 10 minutes to firm up the layers for easier slicing.