Some meters near, the Metro Station Rustaveli, you will find a poster, (a bit destroyed) of Centrum Khinkali, and stairs to go down. Don't worry, it is not something strange or bad, but a realy good Georgian Restaurant, serving home made food.
The interior of the Restaurant, was made after a cinema, which was there, and the decoration is from Old Georgian Style.
The menu is in English and the waiters willing to help you with your ordering. As the name of the restaurant occur, their speciality are Khinkali. With several stuffing inside. The original with lamb, and several else with potato/mushroom, lamb/pork etc. The cost of one khinkali is between 0.30 to 0.70 lari (you have to order at least 3 of them), and enought big to fed up, after 3 or 4.
Also you have to try khachapuri aduri there (marvelous) or salad (we tried with eggplant and nuts, and it was delicous) and of course, as we are in Georgia, Gvino (Wine). They had there homedae with semi dry wine, for 5lari a 0.5litre, so worth to drink it.
We were there twice with my girlfriend, and seriously, we will go there again, if we will be in Tbilisi again.
PS the name of the restauran is Centrum Khinkali
PS2 expect to pay 15 laris, for 2 persons with wine :)
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.