Heat the olive oil over medium heat. Add onion and garlic and cook until soft. Add thyme and carrot and cook until the carrot is quite soft. Add the tomatoes and juice and bring to a boil, stirring often. Lower the heat and simmer for 30 minutes until thick. Season with salt and serve. This sauce holds 1 week in the refrigerator or up to 6 months in the freezer. Yields 4 cups. (I have used sliced beef to this sauce, to make into a main meal)