Okay, here's the skinny: you can go to the tourist Heaven on Seven at 600 N. Michigan, or you can eat at the one all the locals are eating at. In the Garland Building on Wabash in the East Loop, you will find the original location of Heaven on Seven, which actually isn't the original name but refers to the heavenly Cajun-style meal that awaits you on the seventh floor. I believe the original name, still on the door, is something unobtrusive like Garland Coffee Shop. If you're into hot sauce, here is the place to find it in almost any form you can imagine. And when they tell you a sauce is hot, they do mean it.
Here's the catch: you can't eat here for dinner except for the first and third Friday of every month, and they aren't open on Sundays.
Mon-Fri 8:30am-5pm
Sat 10am-3pm
IT IS BUSY DURING LUNCH and YOU WILL WAIT IN THE HALL FOR A SEAT. Don't let this disturb you, as you will be well rewarded for your efforts.