Slow Cooker Lasagna Soup

Ingredients

• 1 lb (450g) Italian sausage, removed from casings
• 1 medium onion, chopped (approx. 1 cup/150g)
• 2 cloves garlic, minced
• 1 (28 oz/800g) can crushed tomatoes
• 1 (15 oz/425g) can tomato sauce
• 4 cups (950ml) chicken broth
• 1 cup (240ml) water
• 2 teaspoons dried oregano
• 1 teaspoon dried basil
• 1/2 teaspoon salt, or to taste
• 1/4 teaspoon black pepper, or to taste
• 8 oz (225g) lasagna noodles, broken into 1-inch pieces
• 15 oz (425g) ricotta cheese
• 1/4 cup (60ml) grated Parmesan cheese
• 1 large egg
• 1 tablespoon chopped fresh parsley
• Salt and pepper to taste
• 1 cup (110g) shredded mozzarella cheese
• Fresh basil leaves, chopped (optional)