Step 1: Cook the Meat

1. In a skillet over medium heat, brown the ground beef or Italian sausage until fully cooked, about 5-7 minutes. Drain excess fat if necessary.
2. Stir in the chopped onion and minced garlic. Cook until the onion is translucent, about 3-4 minutes.

Step 2: Transfer to Slow Cooker

1. Transfer the cooked meat mixture to the slow cooker. Add the crushed tomatoes, chicken or vegetable broth, Italian seasoning, and red pepper flakes (if using). Stir to combine.

Step 3: Cook the Soup

1. Cover the slow cooker and cook on low for 4-6 hours or on high for 2-3 hours.

Step 4: Add the Noodles

1. About 30 minutes before serving, stir in the broken lasagna noodles. Cover and continue to cook until the noodles are tender.

Step 5: Stir in the Cheeses

1. Once the noodles are cooked, stir in the ricotta cheese, shredded mozzarella, and grated Parmesan cheese until melted and well combined.
2. Season with salt and pepper to taste.

Step 6: Serve

1. Ladle the soup into bowls and top with additional mozzarella cheese and fresh basil or parsley if desired.
2. Serve hot and enjoy your delicious Slow Cooker Lasagna Soup!