01 -
Generously coat the interior of the slow cooker with nonstick cooking spray to prevent sticking.
02 -
Add 15 ounces of crushed or diced tomatoes to the bottom of the slow cooker. Arrange frozen ravioli evenly on top of the tomatoes.
03 -
Evenly sprinkle Italian seasoning, salt, garlic powder, onion powder, black pepper, and grated Parmesan cheese over the ravioli.
04 -
Distribute 3 cups of shredded mozzarella cheese over the ravioli. Pour 24 ounces of crushed or diced tomatoes on top as the final layer.
05 -
Cover and cook on HIGH for 2 to 3 hours or on LOW for 4 to 6 hours, until the ravioli is tender and heated through.
06 -
Before serving, sprinkle the remaining 1 cup of shredded mozzarella cheese over the cooked ravioli and allow it to melt.