To prepare sauce, melt butter in a large saucepan over medium heat. Add corn and onion. Cover and cook 10 minutes or until onion is tender, stirring occasionally. Stir in chili powder; cook 1 minute. Stir in tomato; cook 2 minutes. Stir in milk and cream cheese; cook 6 minutes over low heat, stirring frequently. Stir in cheddar cheese, 1/2 teaspoon salt, 1/4 teaspoon pepper, and hot pepper sauce; cook 4 minutes or until melted, stirring frequently. Cover and keep warm.
To prepare chicken, sprinkle chicken with 1/2 teaspoon salt and 1/4 teaspoon black pepper. Place chicken on grill rack coated with cooking spray; grill 4 minutes on each side or until chicken is done. Serve chicken with sauce; sprinkle with chives.