Heat oil in large saucepan over medium heat. Add leeks and onion; saute 5 minutes or until softened but not browned.
Add potatoes, carrot, parsley, dill, salt, pepper and chicken broth. Bring to boiling; reduce heat to low; cover and simmer 35 to 40 minutes or until vegetables are tender.
Working in batches if necessary, puree the mixture in a blender or food processor. Serve immediately, garnished with the chopped chives and parsley. Makes 6 servings.