They left the major anchor stores (Target, Von Maur, Hobby Lobby), turned most of the center of the mall into parking lots, and put up a few multi-store strips around it, and it went from empty to having thriving businesses that have mostly all remained the past 16 years.
This guy has more details and took some pictures of the mall just before they closed it:
Provide the right financial incentives and a developer should be able to do it on terms favorable to the city (vs getting little/no revenue from a derelict mall complex).
Or RoboCop. You choose.