Ripe, full-flavored tomatoes are the essence of this summery, cool soup.
Heat the oil in a large saucepan. Add the onion and carrot and cook 3 to 4 minutes, or until just softened. Add the tomatoes, garlic and herbs. Reduce heat and simmer, covered for 30 minutes.
Pass the soup through a sieve into the pan. Stir in 3 tablespoons of the yogurt.
Refrigerate to cool, then serve garnished with the remaining 1 tablespoon of yogurt.
Soup can be reheated and served warm with cooked pasta and/or a garnish of yogurt.
Serving suggestions are not included in the nutritional analysis.