SPREAD chips onto platter.
COMBINE chicken and barbecue sauce in small microwaveable bowl. Microwave on HIGH 45 sec. to 1 min. or until heated through; stir.
MICROWAVE VELVEETA and milk in separate small microwaveable bowl 1-1/2 min. or until VELVEETA is completely melted and sauce is well blended, stirring every 45 sec.
SPOON chicken mixture over chips; top with VELVEETA sauce, tomatoes and peppers.