1. Heat olive oil in a large pot over medium heat.

2. Add chopped onion and sauté until translucent, about 4 minutes.

3. Stir in garlic and cook 1 minute until fragrant.

4. Pour in crushed tomatoes and broth, then add sugar, salt, pepper, and basil.

5. Bring to a simmer, reduce heat, and cook 15 minutes.

6. Use an immersion blender to puree soup until smooth, or carefully blend in batches.

7. Return soup to pot and add cheese tortellini.

8. Cook tortellini in soup until tender, about 6 minutes.

9. Stir in heavy cream and heat gently without boiling.

10. Adjust seasoning with salt, pepper, or red pepper flakes.

11. Ladle into bowls and garnish with Parmesan and fresh basil.