Fire Roasted Tomato and Basil Soup

12 large (about 2 pounds) tomatoes, stemmed and quartered
1/2 cup extra-virgin olive oil, divided
1/4 cup good-quality balsamic vinegar
12 large garlic cloves, peeled
Salt
1/2 teaspoon freshly ground black pepper
1 cup chopped yellow onions
2 cups lightly packed fresh basil leaves, plus few leaves torn for garnish
2 cups cold water

Preheat oven to 450 F.
Combine tomatoes and garlic in a large bowl, toss with 1/4 cup of the olive oil, balsamic vinegar, salt and pepper. Spread tomatoes & garlic out on 1 or 2 large baking sheets lined with baking paper. Roast in oven for 35 to 40 minutes until very dark in spots. Let cool slightly. In a large sauce pan or pot, heat remaining olive oil, add onions and a pinch of salt. Cook over low heat until onions are soft and golden, about 8-10 minutes. Add the basil leaves and sautee with the onion for about 1 minute. Add tomatoes, garlic and 2 cups of water to the pan, bring mixture to a simmer and cook for about 10 minutes. Season with more salt and pepper to taste. Puree mixture in a blender or use an immersion blender directly in the pot until soup is smooth.
*To make the soup richer and creamier, add 1/4 to 1/2 cup cream (or more if you like) after soup has simmered about 8 minutes so it warms gently. If you are freezing or refrigerating the soup to serve later, add the cream when you reheat it. Makes about 8 cups.