Cut cake horizontally in half. Cut each piece lengthwise into 2 pieces, then cut each piece crosswise in half. Carefully insert 1 wooden pop stick several inches into one short end of each cake piece. Brush off any loose crumbs; place cake pieces in single layer on waxed paper-covered baking sheet.
Microwave white chocolate in medium microwaveable bowl on HIGH 1-1/2 to 2 min. or until completely melted, stirring every 45 sec. Spoon 1 Tbsp. melted chocolate into small bowl; stir in food coloring. Spoon into small resealable plastic bag; reserve for later use.
Spoon remaining melted chocolate over cake pops, turning to evenly coat all sides of each pop. Gently scrape excess chocolate from bottom of each pop before returning to prepared baking sheet.
Add chocolate chips for the bunnies' eyes. Cut small piece off one bottom corner of plastic bag; use to pipe tinted chocolate onto bunnies for the ears, noses and mouths as shown in photo. Refrigerate 30 min. or until chocolate is firm.