PEEL paper liners from cupcakes, if necessary. Cut rounded tops off cupcakes with serrated knife. Cut heart-shaped cutout from centre of each top with 1-inch cookie cutter; reserve cutout for later use.
SPREAD about 1 Tbsp. Cool Whip onto bottom half of each cupcake; cover with cupcake top. Spoon remaining Cool Whip into heart-shaped holes.
DECORATE with reserved heart cutouts and candies. Keep refrigerated.