Sausage Tortellini Soup with Spinach

Ingredients

• 1 lb Italian sausage (mild or spicy, according to taste)
• 1 small onion, diced
• 2 cloves garlic, minced
• 4 cups chicken broth
• 1 can (14.5 oz) diced tomatoes, undrained
• 1 can (15 oz) tomato sauce
• 1 teaspoon Italian seasoning
• 1/4 teaspoon crushed red pepper flakes (optional for extra spice)
• Salt
• black pepper
• 9 oz package of tortellini (cheese or any preferred filling)
• 3 cups fresh spinach leaves
• 1/2 cup heavy cream or half-and-half
• Grated Parmesan cheese for serving