COOK chicken in large nonstick skillet on medium-high heat 4 min. on each side or until lightly browned on both sides.
ADD salsa and water; bring to boil. Stir in pasta; cover. Simmer on medium-low heat 13 to 15 min. or until pasta is tender and chicken is done (165ºF).
STIR in vegetables and 1/2 cup cheese. Cook 5 min. or until vegetables are heated through and cheese is melted, stirring occasionally. Top with remaining cheese; cover. Remove from heat. Let stand 1 min. or until cheese is melted.