HEAT oven to 425ºF.
MIX cream cheese and 1 cup shredded cheese in medium bowl until blended. Stir in salmon and onions.
SPRAY 24 mini muffin cups with cooking spray. Line each cup with 1 won ton wrapper. Fill with salmon mixture; sprinkle with remaining shredded cheese.
BAKE 10 min. or until won tons are browned.