In a skillet over medium heat, cook the Italian sausage until browned and fully cooked. Drain any excess fat and set aside.

In your crockpot, combine the browned sausage, diced tomatoes (with their juice), minced garlic, Italian seasoning, and chicken broth. Stir everything together to distribute the flavors evenly.

Scatter the cubed cream cheese over the mixture in the crockpot. Cover with the lid and cook on low for 4-5 hours or on high for 2-3 hours, until the cream cheese has melted and combined with the broth.

In the last 30 minutes of cooking, add the frozen cheese tortellini and fresh spinach to the crockpot. Stir well to incorporate them into the mixture, ensuring the tortellini cooks through and the spinach wilts.

Before serving, taste and adjust the seasoning with salt and pepper as needed.

Ladle the creamy, cheesy tortellini and sausage mixture into bowls and serve warm.