Broil poblano pepper halves, skin side up, on an aluminum foil-lined baking sheet 6 inches from heat 5 to 6 minutes or until pepper looks blistered. Fold aluminum foil over pepper to seal, and let stand 10 minutes. Peel pepper; remove and discard seeds. Coarsely chop pepper; set aside.
Bring creamed corn and next 4 ingredients to a boil in a 3-quart saucepan over medium-high heat, stirring mixture constantly. Reduce heat to low, and simmer, stirring often, 10 minutes.
Stir 1 1/2 cups chicken broth into mixture. Whisk in softened cream cheese and chopped poblano pepper; cook, whisking often, 5 minutes or until cream cheese melts and mixture is thoroughly heated. Whisk in additional chicken broth, if necessary, to reach desired consistency; garnish, if desired. Serve chowder immediately.