In a medium-sized non-stick skillet set to medium-high heat, add the ground beef and diced onion. Add the salt, pepper, garlic powder, and oregano. Cook until the meat is browned. Don't drain all the liquid off the meat; keep a few tablespoons in the meat to keep it moist.
Spray the slow cooker with non-stick spray.
Add half of the marinara sauce to the bottom of the slow cooker.
Add HALF of the bag of ravioli on top of that sauce.
Add all of the ground beef mixture over the ravioli.
Add the remaining ravioli over the meat.
Pour over the remaining sauce.
Sprinkle over the mozzarella cheese.
Place the lid on the slow cooker. Cook on LOW for 4 hours.
Serve and enjoy!
Video
Notes
Should I thaw the ravioli?
Do not thaw the ravioli.
This recipe has been tested over and over with frozen ravioli and will work perfectly.
Can I use refrigerated-style instead of frozen ravioli?
I recommend using frozen for this recipe if at all possible.
If you can not find frozen, you can use the refrigerated style. You can cut down on the cooking time by an hour.
How can I make this vegetarian?
Use soy crumbles instead of ground beef if desired.
Or you can omit the ground beef entirely.
Alternatively, you can add thinly sliced zucchini to the middle layer for a meaty texture.
What kind of meat can I use instead of ground beef?
Ground sausage - Italian style or breakfast sausage such as Jimmy Dean.
Frozen meatballs - You can use a small bag of meatballs. These bags are usually about 20 ounces, and this will stretch your recipe to feed more.
VariationsÂ
Alfredo lasagna - Use 24 ounces of jarred alfredo instead of spaghetti sauce for alfredo lasagna.
Taco lasagna - Use 24 ounces of salsa instead of tomato sauce. Add taco seasoning to your meat and top with cheddar instead of mozzarella for an easy taco-inspired dish.
Veggie-packed lasagna - Add layers of fresh spinach to this dish instead of meat sauce for vegetable lasagna.