Coat a 4- to 5-quart Dutch oven with nonstick cooking spray. Heat over medium heat about 1 minute. Add onion and leek; cook about 5 minutes or until tender, stirring occasionally.
Add corn. Cook about 5 minutes or until corn softens, stirring occasionally. Add 1 can of the chicken broth. Heat to boiling; reduce heat. Cover and simmer about 20 minutes or until the corn is very tender. Remove from heat and cool slightly.
Transfer half the corn mixture to a blender or food processor; cover and blend or process until smooth. Return the pureed corn mixture to mixture in the Dutch oven.
Add the remaining 1 can broth, the sweet pepper, 1/8 teaspoon black pepper, cayenne pepper, and, if desired, saffron. Heat through. If desired, garnish with snipped fresh chives and/or additional ground black pepper.