In a large frying pan over medium-high heat, brown the ground beef until almost fully browned, about 5-7 minutes. Add diced onion, minced garlic, salt, and pepper. Mix in the jarred tomato sauce and simmer for 2-3 minutes.

Spray the interior of the crockpot with non-stick cooking spray. Layer a thin layer of meat sauce at the bottom. Break the lasagna noodles into manageable pieces and place over the sauce, followed by dollops of ricotta and a sprinkle of mozzarella.

Repeat layering with meat sauce, broken noodles, ricotta, and mozzarella, creating about three layers in total.

Pour a second jar of tomato sauce over the top, sprinkle additional mozzarella on top, and pour water around the edges. Cover and cook on high for 3 hours or low for 6 hours.

After cooking, let it rest for 10 minutes. Garnish with freshly chopped basil or parsley and serve warm.