HEAT dressing in large skillet on medium-high heat. Add chicken; cook 10 min. on each side or until done (165ºF). Meanwhile, blend milk and cream cheese in blender until smooth.
TRANSFER chicken to plate; cover to keep warm. Add cream cheese mixture and lemon juice to skillet; cook 2 min. or until heated through, stirring occasionally. Stir in zest and grapes.
SPOON sauce over chicken; top with parsley.