1. Melt butter in large pot over medium heat 2. Add onions, garlic, salt and pepper; cook until tender, stirring occasionally, about 6 min 3. Stir in the vinegar 4. Add tomatoes, broth, cream and bay leaves and bring to a boil 5. Reduce heat and simmer for 5 minutes 6. Add the tortellini and simmer until cooked (about 3-4 min for fresh, 5-6 min for frozen) 7. Remove from heat 8. Remove and discard the bay leaves, stir in the basil 9. Ladle into bowls and top with more basil and parmesan cheese if desired