Hands On: 20 minutesTotal: 30 minutesHeat oil in large saucepan over medium-high heat until hot. Add onion and carrots; cook and stir 5 minutes.Add tomatoes, broth, sugar and dill. Bring to a boil. Reduce heat and simmer 10 minutes, or until vegetables are tender, stirring occasionally.Place portion of soup in blender or food processor container. Cover and blend until smooth. Repeat with remaining soup. Season to taste with pepper. Garnish each serving with yogurt, if desired.