Heat the oil in a large saute pan over medium heat. Add the onion and cook, stirring for 5 minutes. Add the garlic and cook for 1 minute longer. Stir in the tomatoes and basil and continue cooking for 10 minutes.
Add the cream, sugar, if using, and salt and pepper, to taste. Continue cooking, stirring occasionally, for 5 minutes longer.
Serve with hot cooked pasta.
Garnish with fresh chopped basil, parsley, or Parmesan cheese.