Cut peppers in half lengthwise; remove and discard seeds and membranes. Place peppers, skin side up, on a large baking sheet; flatten peppers with palm of hand. Broil 5 1/2 inches from heat for 15 to 20 minutes or til charred. Place peppers in ice water until cool. Remove from water; peel and discard skins.
In a food processor, process sweet pepper and remaining ingredients until smooth, stopping to scrape down sides. Cover and chill up to 5 days.