CUT bananas in half crosswise. Insert pop stick into cut end of each banana half. Place on tray; cover. Freeze 3 hours or until firm.
MICROWAVE chocolate and butter in small microwavable bowl on HIGH 1-1/2 to 2 minutes or until chocolate is almost melted, stirring after 1 minute. Stir until chocolate is completely melted. Pour into tall glass.
DIP frozen bananas into chocolate mixture, turning to evenly coat. Immediately roll in sprinkles. Place on wax paper-covered tray. Serve immediately. Cover leftover pops and store in freezer.