 TO INDIAN ALFONSO MANGO AND PURPLE YAM TREATS. ONE UPSCALE KOREAN EATERY OFFERS A SWEET CORN ICE CREAM POP SHAPED LIKE A CORN COB SANDWICHED INSIDE A CHARRED CORN COOKIE. PRICES CAN'T BEAT THE GOOD HUMOR, MAN. THE SWEET TREATS RANGE FROM 10 TO 20 BUCKS. DEBRA RODRIGUEZ, CBS NEWS, NEW YORK.