Preheat the oven to 400 degrees F. In a large, 14-inch, oven proof frying pan, combine all the ingredients. Stir to blend then transfer to the oven and cook until the tomatoes begin to caramelize, about 30 minutes. Remove the skillet from the oven and stir well. Return to the oven and continue to cook until further caramelized and much of the liquid has evaporated, about 30 minutes longer. Remove from the oven, cool slightly, and transfer to a food processor, in batches if necessary, and process sauce until coarsely pureed. If the sauce seems too thick, thin with a bit of water or chicken broth. Use immediately or cool completely and refrigerate for up to 4 days in a non-reactive, airtight container. The sauce is great on pasta as well as pizza and even makes a great dipping sauce for hors d'oeuvres. If you prefer a less rustic sauce, puree completely as described above and strain.