Ingredients
1 bag (25 oz / 700 g) frozen cheese ravioli1 lb (450 g) ground beef1 jar (24 oz / 680 g) marinara or pasta sauce1 can (14–15 oz / 400 g) crushed tomatoes, optional2 cups shredded mozzarella cheese½ cup grated Parmesan cheese1 small onion, finely chopped2 cloves garlic, minced1 teaspoon Italian seasoning½ teaspoon salt, or to taste½ teaspoon black pepperCooking spray or a little olive oil
Instructions
Cook the beef: In a skillet over medium heat, cook the ground beef with the chopped onion until browned. Drain excess fat, then add the garlic and cook for another 30 seconds.Prepare the sauce: Stir in the marinara sauce, crushed tomatoes if using, Italian seasoning, salt, and black pepper.Layer the ingredients: Lightly grease the slow cooker. Spread a thin layer of meat sauce on the bottom. Add a layer of frozen ravioli, followed by meat sauce and mozzarella cheese.Repeat the layers: Continue layering the frozen ravioli, sauce, and mozzarella until all ingredients are used. Finish with mozzarella and Parmesan cheese on top.Slow cook: Cover and cook on LOW for 4–5 hours or HIGH for 2–3 hours, until the ravioli are tender and heated through. Cooking times vary by slow cooker, so check for doneness toward the earlier end.
Let it rest: Turn off the slow cooker and let the lasagna rest for 10 minutes before serving.Serve: Garnish with fresh parsley or basil and serve hot.Tips for the best resultsUse frozen ravioli directly; do not thaw them first.Avoid stirring the layers too much to keep the ravioli intact.Check that the center is thoroughly heated before serving.