In a medium pot or Dutch oven, heat over medium-high heat and add the Italian sausage. Use a wooden spoon to break it apart and cook for about 5–7 minutes, stirring occasionally, until browned and fully cooked.

Add the chopped onion and minced garlic to the pot. Sauté for approximately 3–4 minutes, until the onion is translucent and the garlic is fragrant.

Stir in the salt, black pepper, and all-purpose flour, mixing well. Cook for about 1 minute.

Pour in the tomato sauce, stirring well, and bring to a gentle simmer for 2–3 minutes.

Carefully add the cheese tortellini, stirring to ensure they are well-coated in the tomato base. Cook for about 5 minutes.

Lower the heat and gently stir in the heavy cream, baby spinach, and kale. Cook for an additional 2–3 minutes.

Ladle the soup into bowls and garnish with fresh parsley if desired.